At Level30, maxed out Gyarados at CP2853, closedly followed by a not-so maxed out Dragonite @ CP2780 as Dratini candies are hard to come by and a not-so maxed out Rhydon @ CP 2629 as I only power up as an alternative revival technique and only did the power up after the Meta game in favor of Rhydon.
My 4th is another Gyarados (not yet maxed out), followed by interesting bunch like Exeggutor, Alakazam, Arcanine and Snorlax (CP2300-2500)..
To round up my Top 10, currently at 9th place, a high-level eevee turned Flareon (not a wonder so not gonna power up) and a high-level Pinsir caught in the wild @CP2200+.