Yeah, Mantis Leap from S&F lets you make a jumping charge attack which gains double your Str mod to damage. You have to be a 7th level monk though, and it doesn't mention anything about jumping over people. I think it is reasonable that if you can jump high enough you should be able to go over enemies though. The primary benefit of Mantis Leap seems to be the extra damage, so I'd figure just about anybody can perform a jumping charge.
I don't think you should have to worry about the arc of the jump all that much either. If you want to clear the front line and come down right behind them maybe you jump at a 60 degree angle instead of a 45 degree angle. I don't think that's a big deal, and as far as charging goes you'd still have a ton of momentum on your way down.
Heck, after all the fighting games I've played I'd probably even allow a vertical charge where you jump straight up and come down on an enemy with a charge attack. Obviously all of this stuff could draw AoOs, but it could add a nice cinematic flair to combat IMO.
If I were going to create a feat it might allow you to combine a bullrush type attack with a jumping kick (or whatever) so that you could "clear out" a space for yourself to land even in tightly packed enemy formations. Of course failure would leave you prone in the middle of a bunch of enemies. The Drunken Master PrC already has a similar but more powerful ability called corkscrew rush, so I don't think that a feat allow a jumping bullrush attack would be out of line.
. But I think at least it is a damn difficult maneuvres, and as such it deserves a special feat to be performed, IMHO.
