When you don't do akusla you do kusala?
I think generally speaking you are on the right track. Your question seems very clear to me and your logic is valid.

Don't do akusala, on all levels from coarse - to very subtle, exactly this was my path, this can be your path. You don't need to worry about kusala, as long as you put serious effort in not doing akusala, you will advance.

Now, "serious effort" is very serious. There is akusala hiding inside kusala, and there is kusala hiding inside akusala. So you should be very bold and very brave. I see you are making progress since you joined.