Recently I gotta say the create mod is very impressive and I've enjoyed my time with it
That's where, imo, its super important for modpack makers to properly balance stuff around the other mods in the pack. Tinkers construct just got ported to mc version 1.16.5 and there is a new similar mod called tetra which provides similar but different functionality.
More recent editions of mc have the mod "little tiles" and "chisels and bits" which allow you to place what are somewhat similar but better to classic microblocks. Little time iirc lets you go down to a 1/128th of a block.
You may also like the conquest reforged mod. It has a huge number of textures and archetecture elements. The cocricot mod and texture pack are very good if you would like to make something more modern. Here are a couple links of examples for things done with chisels and bits and little tiles
The mod where if you chop out the base of a tree the whole tree "falls"
I can't remember what it's called. Been years since I've played minecraft
There are so many at this point lmao. Treecapitatoe, treefeller, ftb omnimine, the list goes on.
Never played Gregtech. I fell in love with IC2 and Buildcraft back in the days of Tekkit Classic and have never really moved on
Oh damn an old :P There are a few 1.12 modpacks that are doing a pretty good job of a replicating the classic tekkit experience with the less jank of modern versions of the game.