Oooh so many!
I also use grapeseed upto 15% in a couple of recipes - one, which I am making right now also has neem and blackseed oils - here it's in the same cost group as avocado and almond. Not so bad, but too much to be in all my regular soaps.
Some here use high oleic safflower instead of olive oil so that's another one to look into.
I know someone who regularly uses soybean. It costs slightly more than canola here. Apparently the lather is awesome, but it's another of those prone to DOS.
I'll leave the rest for the others who are nearer to you. My location isn't a reliable basis for cost, and a lot of those oils aren't even available hehehe