I wish games with multiple rounds would notice that I mastered the easy levels, and let me skip them.
I'd like to pass a certain checkpoint (something fairly hard) and never have to play the easy stuff again. You'd just start right at the hard part. Multiple checkpoints at increasing difficulty might be even better.
Blizzard seems to agree with this: in Starcraft 2, all players start with six worker units already built. No one has to prove they can sit there for two minutes building drones to get to the interesting stuff.
Apps that do this show respect for my time, which helps me love them.