I can't see where flint-vs-percussion is a critical factor with respect to balance, sight radius, etc.
I have two pistols with 10 inch barrels - the percussion .45 T/C Patriot has an 8 inch sight radius, the Kentucky style .36 flinter has a 6 inch sight radius. Both have wide notches, and substantial, tall square front sights that you can see without using your imagination. Both guns are decent performers out to 50 yards for paper targets. The flinter would probably be better with an 8" sight radius rather than the 6" it has.
Both guns have decent trigger pulls - T/C set trigger, flinter about a 2 or 3 lb pull simple trigger. In contrast, years ago I had a Lyman Plains pistol with a pretty heavy single trigger and I could never get it to group even at 25 yards, much less 50.
So, a 10" barrel strikes me as about right, and I'd give some thought to sights and ensuring I had a decent trigger pull on the gun, and for dispatching game, would limit range to 25 yards. Flint would be a concern only in that like any flinter, you want a good sparker for fast ignition. As to carrying in the field, take care that you have some way of ensuring the ramrod won't fall out of the thimbles and be lost. It's happened to me.
SCL