The primary reasons people don't come back on axis from corked spins is either they don't stay tucked or they don't keep their head in the spin. I don't have time to explain all of it right this second but When you throw your spin, keep it tucked tight as possible and keep looking over your shoulder. This should bring you around if you're throwing your cork right. Also, 7's are easier to get back on axis because the rotation is more natural and it is easier to spot your landing. However, if the jump isn't big, you take what you can work with...
BTW, I do a lot of coaching and would be happy to give advice if you ever message me. Gotta run now though...