Starly, which evolves into Staravia at lv.14 a which then evolves into Staraptor at lv.34- Route 201
Shinx, which evolves into Luxio at lv.15 which then evolves into Luxray at lv.30- Route 202
Budew is a good choice for a grass type if you didn't choose turtwig.- Rote 204 NOTE: After this evolves get a Shiny Stone at the end of the Iron Island side quest. It will become one of your best Pokemon.
And your starter.- Talk to To ur rival and eventually you'll get to this point. Any choice is good i chose Chimchar at first but although i hate it, its probably the easiest to use just because it gains the Fighting type later on.
Ponyta- Route 206
Machop- Route 207 IDK bout this unless u can trade if you can great, if not then id find something else.
Abra - gonna have to look hard but 203 and 215 also its a ***** to train and catch since it only has Teleport (a non attacking move in which it Teleports or gets out of every battle). So to train it keep it in the front of your Party and when a Pokemon appears or a Trainer battles you switch Pokemon to one of your strong ones and kill the other Pokemon Abra and your Pokemon with share EXP. Also if you can trade then trade this because it will evolve into Alakazam which is just beastly.
Shellos, which evolves in Gastrodon at lv.30- Route 205 if you want a pink one, 213 if you want a blue one.
anyway hope that helped good luck.