This is a great question and the best answer really is - it depends.
There are techniques that can sometimes change the response of the entire instrument, improve elements of the performance, etc. The actual model of piano that we are discussing will dictate possible changes.
Lastly, you specifically asked about a better bass response and suggested a different rib design. Yes, this is a technique that might help. It all depends on the instrument. To me, balance is the key in a small piano. I played a small Chickering worked on by Ed McMorrow that impressed me. His solution included hybrid stringing.
Tell us more about the piano in question. If we can’t help you here, we can certainly direct you to others.