Ok, I have played to the first gym, and thats what I got:
The early game lacks of difficulty, I've went to the first gym without leveling up, maybe some better placed trainers would correct this(At least two that directly block the way, so the player must fight them).
Also, the first city (forgot the name, srry), needs to be remodeled. It needs some fences to the left, having just the trees doesn't really looks great, so you should add something there.
For the other things, it looks ok, also Snivy it's very cute in GSC style ^^
Good luck with the hack!
PD: If someone needs to know, it's for 1.1 crystal, 1.0 will give some errors and get stuck at a glitchy boot logo.