Years ago, back in Beta, I used to play on smaller economy and building based servers. It was very fun, especially when I was new to the game. Since then, I play in bouts. I go a few months not playing, then only play it for a week or two.
I used to only play vanilla singleplayer, or on servers with plugins. That got boring, so I went through about a year of playing singleplayer on and off with various mods. After that got boring, I went back to vanilla, and that's where I'm at now. At the moment, I mainly build small projects on superflat worlds.
Tbh, most servers today are cancerous cesspits full of micro transactions and generic copy/paste worlds. Kinda like DarkRP on Garry's Mod is like right now.