Lets talk about the length first, the blade being ten inches is fine, make the handle long as well, l'd go minimum 6"to help balance the feel and the look of the knife. It just looks better with a large blade to have a large handle. At least to me.
l forged two Arkansas Toothpicks with 12" long double edged blades and 7" handle on one,(haven't finished the 2nd one) and the knife balances right on the guard and l accomplished that feat with a heavy brass bullet shaped pommel. With the knife balanced that way it handles like it was lighter, the brass pommel is a counter weight to the blade and it is quick and easy to twirl, though kinda dangerous.lol
l didn't make it as a chopper, but a fighter and specifically for bears. My son encountered a few of them out trout fishing so he wanted something that could dispatch a bear and that 1080 blade could do that, though l told him a bigger gun might be more appropriate. lf you can do a full grind up to the spine that would make the knife lighter and certainly will make it cut/chop better. Good idea to grind back most of the blade before HT, l always did, do you still grind with the 2x42 grinder?
As for quenching in water, l wouldn't, canola oil is comparatively cheap. As for the clay you can just edge quench the blade as well or draw the spine back with a torch. The clay may make a nice hamon if you go that route, but l'm not an expert on hamons, but it should leave the spine relatively softer than the edge. Quenching in canola should still draw back the spine enough, especially after temper.
l presume you're using a forge for the heat treat? The reason l said 3/16 thick is you won't need to worry if your spine is thick enough. l made the Arkansas toothpicks from 3/16 and tempered them back more than l would a regular cutting knife in case if it hits the rib bones it wouldn't break, but its pretty hard to break a 3/16 thick blade Hunter. Here's a link to it.
https://www.flickr.com/photos/139620...7671162338314/
Keeping the knife balanced will make it better handling since fast is what you want, but then look at a Kukri, really blade heavy and its still the fighting knife of the Nepalese Army. Those blades run 1/4 to 3/8 thick. It's all in how much you train with it, but they are awesome choppers. l tried one once to chop some firewood and it was as good as a small ax.