The key to the whole Prequels is Anakin and Padme, and would the audience care about them? In the end, I really didn't care about their struggles and their eventually fate at the end of the Episode 3, so it really makes it tough for me to enjoy 3 movies essentially about them.

That is why I hesitate to these OT vs PT debates because they are essentially 2 different trilogies with 2 different characters, so its just natural that the viewer may only care for the OT characters, and not like the PT characters, or vice versa.

It will be interesting with the ST and the structure from what is leaking on the internet (Luke, Leia, Han are prominent in Episode 7 and their kids will be the leads in Episodes 8 & 9).