One of the RPs that I appreciate more now than when I first joined was Glaciate by PastelPhoenix (if he still goes by that). The whole magic system and its setting were things that I honestly just took for granted. The idea of mixing ingredients for spells probably seemed complicated and restrictive but it was a nice way of keeping players abide on established in-game fundamentals while still promoting room for creativity. Beyond mechanics, the aesthetics were also neat; just the idea of having magical wands being reimagined as fucking guns was so silly yet awesome. Kinda wished I was a bit more involved and committed when it was still active, especially since this RP did get a lot more player input than I usually see in most RPs.
Kiyo's RP Off the Menu was also a RP I enjoyed notwithstanding its critical issues (progression was hell because GM literally had to post every time a player breathes). Sure, the concept is easily the most mundane - literally just a bunch of dorks working at a diner like compare that shit to a bunch of magical teens fighting a giant squirrel or superheroes, but that mundane setting sprinkled with just a bit of the supernatural was pretty exotic. I don't know, I guess the most memorable and fun RPs are the ones that branch away from the popular genres though I don't think that is or should be an indicator of quality.
I guess the first RP that I "officially" joined will always be one that I'll remember; 'International Idol Star' by Disclosed or Junier (or whatever her current name is here) is pretty notable to me for literally being the only Pokemon RP to solely focus on coordinators and contests, whereas everything is mostly just a Mystery Dungeon simulator or a Journey. Or a really gimmicky crossover with another franchise. Whether it was good or not, the RP's lifespan was as long as your typical RP and died before it really got anywhere. I think this RP was the RP that sorta made me enjoy the idea of joining RPs as a "troll", or specifically a character that completely clashes with the RP's premise and setting. Like for this RP, instead of signing up as a talented prodigy who's in it to win it as any sensible player would, I just dick around with a clown.
I was also fond of Ice's epic Bowling RP. Actually I'm just meming. It sucked. The ending made me super depressed. Thats not positive so ill end this by saying I still think you're cool, Ice.