I have a 13" AK that I love for a small khuk. It doesn't behave like its bigger brothers, but it offers more snap than a comparable straight knife. I find a lot of diminishing on a non-job specific knife over the 12" mark. That is to say, a khuk smaller than 12" overall feels weird. A straight knife designed as an all around camper feels cumbersome.
I usually pack the 13" AK when I'm doing yard work. A couple of months ago, I had to send a baby bunny to bunny heaven because I had accidentally run over his nest with my mower and mortally whacked him pretty good

The AK made it a quick slide to the other side for him without making me feel like I was having to get all close and personal to the deed. Anything smaller would have made it a messy job on my soul.
If we're not talking about a chopper, I much prefer a smaller lighter belt knife like a SARGE/KPH or any of the R-Series. Unless the knife is super balanced, that is. I have a Fiddleback Woodsman that is very much in the do-it-all-jack-of-all-trades size, but the balance, sharpness, and blade shape make it one of my best performing camp knives. Pairs nicely with a larger khuk, a SAK/multitool, and a kit .22 pistol.