i'm in your conscience
Awesome sauce. In fact, I think I might make that favorite challenge. I love using favorites. :> Only thing weird I find about it is trying to think of 6 favorites for each type. Would we put them in our sign up post? That's what I would think, cause people could lie and say "oh my 3rd favorite fire type is Ho-oh". Which also leads me to question whether or not legendaries are allowed. I say they should be, since they can be considered a favorite. But then again, I wouldn't want the person assigning my types to really know my favorites, cause they might purposely assign them so that I'm stuck with Mareep, Sunkern, etc. (They're not my favorites, just an example. XD)
Only reason I'm asking is cause I'm actually trading my SoulSilver stuff onto my Platinum for storage cause I really think I will start this challenge. :) And since you came up with it, I wouldn't wanna kill the challenge you made. XD
Too much grinding for my tastes, but a similar challenge to that is the Catch'em All Challenge, only that one requires a full Dex and level 100 iirc.