I'd agree that they should've balanced the Guardians a bit more than just being more on Star-lord. And that I get why, as the story has focused albeit more on him even though he is the leader of a colorful space-team that kicks ass and call's names.
I mean, when you can save the galaxy twice, you would atleast want a bigger payraise to allow it to happen.
As for Ego..I'll just talk on spoilers.
I honestly, when first hearing about Ego being Peter's father caught me off guard and that I was somewhat hesitant. This film, is about family. And that with more time for Yondu, we can fully understand his and Peter's relationships, and that I wouldn't be surprised if we see him in a flashback for Infinity War/Gauntlet (I know that's not the official name of the fourth, but it might as well be).
That said, the ending pulled a large punch, as they handled the death of Yondu gracefully and in one of the best way's in the MCU thus far. And, that they did something that honestly puts Spocks Funeral to shame.