The Ki-61 is one of the best best planes in the game and it is a 25 ENY. Only one time I have seen the ENY near 30. Hub, myself and a few other Bish switched to Rooks. Most Rooks were laughing that we switched. Within a few minutes, the Rooks that were the tower just logged.
ENY rarely affects me. The A8 is 31 for crying out loud. The F4, G-2, G-6 are 30. There is a plane at the higher levels of ENY for everyone, you just need to step up to the plate and fly em more.