>>34615230Sage Dev here. Depends on if you're talking about ingame or in a competitive sense (there is a showdown server, but it's down at the moment).
For the most part, I'd say to forget anything that doesn't evolve before 30. Although Alpint can hold its own pretty well.
Fawning and Pebblosa are good early route mons.
Fowattle, Carajoule, Trenchula, Scubug, Dreamdery, and Hoppanero are pretty good, but can some can be a pain to train or struggle in certain areas.
Platypow and Telsion are good if you're struggling with the second and third gyms.
Competitive-wise, Basilect, Comossus, Platikhao, Eluchadon, and most of the legends are some of the best mons, but they'll probably be nerfed by the final release.