Since I just started a new account last month, I've only so far raised a few Pokémon to CP levels above 1500. These include Vaporeon, Golem, and Snorlax. Vaporeon is top favorite so regardless of its stats, I knew I wanted to raise one. The other two were for Pokedex/capture.
It's helpful to raise a Pokemon with 2 or 3 stars from the appraisal, but some species are just better than others. My near perfect Raticate isn't going to be as helpful as Snorlax. My Vaporeon will also be more helpful than a Flareon (water typing more useful).
Good Pokémon to raise include:
- Glass cannon / sweepers like Alakazam, Gengar, Jolteon, Infernape, Excadrill, Sceptile
- bulky sweepers like Swampert, Electivire, Machamp, Salamence, Rhyperior that specialize in either physical or special
- bulky tanks like Vaporeon, Blissey, Donphan, Snorlax, Clefable, Dragonite
- Metagross, Tyranitar, etc are bulky and strong all around
Since the above listed may be rare, maybe raise something common in your area that isn't a Wurmple. I tend to find a lot of Growlithe and Geodude. There may be tier lists online for what's recommended to raise.
