I've never used the Sora. It's no problem for me to shift from the drops with Campy but that's really not the issue.
You state you're happy with the fit of the bike, right?
You have, I know from previous posts, other physical concerns.
What I would do if I were you is rebuild the bike with a better group. Then if you want to later use this new, better group as your basis for a build up of a new bike.