What would be some good tiles?

I'm making my second terrain map (First one was a year or two ago before I quit) and I'd like some help with the tiles. The type of map is a mountain like map that has a big river and a city that's just starting to grow. I'd like to use the Lorderon Summer tile set with Grass and Vines from the Ashenvale one, but I'd have to remove something.

Before I start a map I'd like to know if I can increase the maximum tileset to something else, and if there some suggestions to some one new to terraining

Crops are always a good choice, just incase you have a big empty spot, make it a farm.

Use WEU :D

Does it work with 1.21?

You can get grimoire and replace one of the files with WEU (Or something, ask PitzerMike / PipeDream - whatever his name is >.>)

PitzerMike.