I´d like to add a suggestion:
-Essentials made:
--Pokemon Crimson Skies (Good story, nice interface, non laggy 3d sprites, currently has 6 gyms) --Pokemon Lithareon (a young Prof. Oak is your rival)
-Rom Hacks:
--Emerald Omega (Expanded Dex- some Hoenn/Sinnoh/Unova pokes + Sylveon added - VERY very hard)