The challenge doesn't really seem all that good. The only thing I can see about it that really makes it a challenge, is that you have to only use Pokemon from the first route in the game, which is essentially the Second City challenge, which is kind of pointless.
Maybe something else for that dream themes challenge. I'd call it the Rainbow challenge. Essentially, you'd play the game like a rainbow.
- You must have six Pokemon in your team. They must all be Red, Orange, Yellow, Green, Blue and Purple.
- You must catch them in order of the rainbow.
- - - If, for some reason you can't find a red Pokemon early in the game, you can choose another colour to start with, such as blue, but it must still be in order (so if you start with blue, you must go purple, red etc.)
- One of your Pokemon must be able to learn Rain Dance or Sunny Day via level.
- - - If you're playing R/B/Y where weather didn't exist, then two of your Pokemon must be able to learn Ember and Water Gun.
- In addition to the colours, 1 of your Pokemon must be in the Plant type Egg Group.
- Heavy fire type moves (base 80+) are banned from this challenge. You don't want a heat wave during the rainbow, do you?
- Ghost/Dark types are banned from this challenge, as they will darken the rainbow which you have created.