If you can try, whatever feels better.
If you can't, probably better to size down. Adding some inches here or there via a different saddlepost, handlebars, headset etc. is possible, but you can't shrink the frame.
Best way in my opinion is warm water and a metal pot scrubber (like this)
Specialized chain cleaners do apparently work from what I can tell, but they run expensive and water and a pot scrubber has done a better job than any homebrew solutions I ever tried with the added bonus of not having to fuck with additional caustic or otherwise toxic chemicals.
I'm sure it'll deterioate the chain marginally faster than using a chemical solutions because you're just rubbing metal together but then who gives a shit.
Whatever floats your boat then, really. Any bike'll do that, it just depends whether you want to be a bit more comfortable (like a dutch cycle) or a bit faster.
They get a bad rep from cycling enthusiasts because many of them are elitist assholes, but I think a hybrid / trekking bike would do you well. It's the jack of all trades of bicycles, really. Maybe see if you can get one with internal gearing as those require way less maintenance. It's not perfect at anything, but you can pretty much ride it everywhere at a decent speed and comfort.
Well then I'd start figuring out what kind of bike you want for getting around on. I mean I'm a big fan of the dutch cycle as a means of transporation because they tend to be bulletproof as far as parts go and have very low maintenance.
Basically the farther and/or more out of the city you want / need to go, the sportier your bicycle should be. I mean roadbikes are fun because they're fast, even in the city, but any gains of speed are pretty much destroyed because you'll wait at the same traffic lights anyways and whether you get there doing 30kph on a roadbike or 17kph on a dutch bicycle is kind of a moot point as far as time savings go.
What's a usual trip look like for you as far as height difference, infrastructure and type of roads go?
Don't think the overlap of people trying to get rid of a getting-around-bike and wanting a BMX is too high, so maybe sell the BMX and use that money to purchase a different bike or if you have the reserves, purchase a different bike and then sell the BMX?
Yeah, same. I currently struggle to do joyrides. I at least want a coffee or something at the furthest point.
What usually helps me is combining it with something that gives me a destination. Geocaching on a bicycle can be fun, as can be photography if you're into that.
Or maybe use a randomizer to spew you out some coordinates near you and cycle there and then be mindful. You know, smell the roses, watch some birds. Just actively be somewhere for 5 minutes or so before you move on.
Picnics can also be nice.
I've only ridden one of the EU legal ones that you have to pedal and they support you up to 25km/h but even that was fun as all hell. Seriously, if you ever ridden a bike down a hill it's that at all times as long as the battery holds. They're genuinely insanely great vehicles for transporting one person and some cargo.
I think they have great potential to replace many, many car trips, especially if you get into Cargo E-Bikes. The problem currently, imo, is that they're seen as expensive hobbyist things because the infrastructure to allow safe travels on a bicycle isn't there - at least here in Germany. People will put up with shitty weather, they won't put up with nearly being flattened by a car on every trip. It's the whole thing where a 1000€ Bicycle is a rich man's toy but a 20.000 € car is basic necessity. Due to how the country is, this is kind of true in some cases allthough by no means as much as people tell themselves. Like even if only for fuel savings, the E-Bike will amortize itself fairly fast.
And at least for my area, this tracks. Only time I ever see E-Bikes is with middle-aged or old people using them for a nice ride out through the national parks here on the weekends - which is a good thing, but it's not the revolution of mobility I'd like to see. It seemingly doesn't replace car trips, it's just a somewhat expensive hobby people do on the weekends. I think this is equal parts shit infrastructure and brainworms.
As for the hand wringing about how unsafe they are, that's just the typical bicycle bad victim blaming bullshit talk. You'll get your "oh nooo the pensioners can't be trusted to do 25km/h on a bicycle, they don't know how to deal with that" when no one bats an eye on grandpa joe barreling his Mercedes through the city at 50km/h. You'll see statistics about injuries increasing but then you find out it's not them eating shit from talking a corner too fast, it's mostly them being hit by cars because the infrastructure is garbage.
I do think they need more regulations as far as batterys are concerned. We're seeing the first wave of E-Bikes being trashed like 5 years after they're bought because the battery is dead, it's built in and can't easily be replaced and that's if you even find a replacement for whatever propietary bullshit the manufacturer put in there. This is insanely wasteful nonsense, bikes hold up waaaaay longer than that easily even if you abuse the fuck out of them, but with the battery dead and irreplaceable you do just end up with a heavy-ass bike nobody wants. You might be able to salvage parts, but that's kind of out of scope for most people.
I will not lie though, I do feel smug when I overtake an E-Bike with my wattage bazookas because let me have that, I need to struggle against the wind near constantly.
Tinkering with my bikes.
I'm kind of in a slump as far as actually doing anything goes currently and don't get to riding much apart from work and errands and stuff, but I do quite like tinkering with them currently.
Researching parts, replacing or fitting parts, more-than-usual maintenance and such. There's always some way to eek out a few more watts or otherwise improve a bike. Currently considering changing the chainring on my singlespeed because my RPM top out a bit below the speeds I'd like to go, ordered some fenders that'll need fitting and different brake pads because the current ones are a fair chunk less effective than I'd want them to be in the rain.
Also recently built up an old bike as a grocery getter and I'm still thinking of a better, more convenient way to secure a huge crate on the back that can also be taken off. It's a neat project because as far as I can see, there isn't really a guide for what I'm doing so I genuinely have to figure it out myself and not just buy parts and follow an instruction manual.
The bus stop there is closer to an entrance than some of those parking spaces
Imagine building your car centric infrastructure shitty enough you not only manage to create a last mile problem for a parking lot, you actually manage to have it be worse than the one for public transport in the US
Furthest parking space in the lot on the top right is half a kilometer away from an entrance lol.
How 'bout in the middle of a fucking pandemic the guy in charge actually works instead of fucking off to Delaware about half his weekends
Fucking love me a leftist-fallen-out-of-time guy that you meet in a divebar at 2am
Speech full of formerly socially acceptable slurs, heart in the right place and about two shitty conservative opinions uttered away from starting an honourable fistfight.
Value Select is really good. Here's some favorites, Rejoice!
Seriously folks, bicycling is a sport where not only can you eat during, there's a good chance you should
Depends on what you consider long distance. Ya boy ain't no randonneur (yet)
Longest distance in a day I ever did was ~120km with a fully packed bicycle and against headwinds the entire time. By the time I arrived I could literally not eat enough to feel replenished.
Longest multi day trip was about 450km over 5 days. I want to do more but you know, pandemic.
Why the fuck is Jordan Peterson wearing a telnyashka?
No Gods, No Matrix!
EU based, but reasonably good ones can be had new for about 500€. I'd assume it's not that different elsewhere in the west. Used market is a toss up for where you live. I've done multi day tours over hundreds of kilometers on a 250€ used trekking bike and it has never failed me. Something like this would probably be a good fit for your needs. . Aluminium frame, 3 gear internal hub and the hydraulic disc brakes are nice and you can fit a proper rack to it.
Rule of thumb is you want a bike from a brand that separates their models by years. Department store bikes are often called BSO - Bike Shaped Objects - because they tend be assembled wrong and the components fall apart after about a year.
If you find one, feel free to throw me a PM and I'll tell you what I can from looking at it online.