imo you should, before nuking your account, make a backup of everything you said, and maybe some of the surrounding context, and then host it on a website. Just make sure your website is all properly indexed, and shows up when you use the right search terms. I have no idea what the legality of such an undertaking would be, but it would be cool. Or, if you don't want to bother with that, you could try writing some blog posts based off of the correct answers you gave to obscure questions.

But really, it all depends on what you did with you Reddit account. If you answered people's obscure questions, you should keep that information. Would someone look up a question you answered? Did you talk a lot in more technical subreddits? Did those arguments you have result in any positive change? But if you spent all your time on big threads with thousands of other people replying, or did a bunch of lurking, maybe your account isn't worth keeping.

If you account is only of value to you, maybe just downoad a copy of everyhting you've said on there, then nuke your account with some tool.