>>36067438All three starters are pretty good in battle. Chimchar is the hardest one probably, but only because the first gym is rock and the best thing you get before is psyduck or geodude iirc.
The game starts awfully slow, so be patient. It gets better after the 2nd gym and remains pretty solid for the most part. You'll also most likely find your team suddenly underleveled at some points, and grinding can be slow and boring. Also keep in mind from the beginning that you WILL need an HM slave, especially when you start venturing deep into Mt. Coronet