Trying to decide which Eggy I should invest in by powering up, help!

This is only about a week of stardust collection for a moderate player. And candy is no problem if you have stumbled upon a nest once. In any case, you will spend much more to bring any of them up to level 35+.

Seeing how my own eggies are among my most often used attackers, I too would be tempted to go for the highest quality.