Dual pump upgrade

I have a 15K size pool with a spa that right now has a HSQ125 (1.25 total HP) pump that handles the everyday pool maintenance. This pump has a housing Starite Duraglass P2RA5E-181L rated for 1HP pumps. This setting has a 2nd pump that handles the bubbling jets in the spa (hardly ever used). This spa pump is a HSQ165 with a total 1.65HP, and its housing is a Starite Duraglass P2RAF-182L rated for 1.5HP. The filter for this system is a Hayward C900 rated to handle 90 GPM.

Yesterday my main pump HSQ125 burned out and needs to be replaced, and since I always wished that my system had a little more power for better water movement, my question is; can I move my spa pump (1.65HP) to the housing of the main pump and purchase a stronger replacement pump for the spa?

I understand that because of the check valves installed in my system to handle the 2 pumps turned on at the same time, for the spa bubbles to work properly the spa pump must always be stronger than the pool pump to close the check valves, so is it possible for me to get a let’s say a 2.20HP pump to replace the spa pump? That way I upgrade the HP of both the pool and spa pumps???.. Tubing is 2 inches, so I’m not worrried there, but the new pumps will be rated higher than the housing on both ends, and will this filter also be enough to handle the extra load?.. I’m pretty handy with installing the equipment, but it’s the math and system over power that scares me. Don’t wanna destroy my good running system… Any recommendations? Thanks in advanced