There's different kind of fittings you could use to avoid those 90's at the top if your pump. I'm a pool/hot tub builder and would never put that kind if back pressure on a pump return, I would use a sweep 90 slp x skt to save space. The difference in your gpm and head pressure are remarkable, your losing a lot of flow here and, in the pool industry at least, we'd look at this as future issues with the pump as well. Overheating is the number on cause of pump failure and back pressure is the number one cause of overheating. That volute is regularly available at pool/hot tub stores if you need a replacement. As well, the main seal in that pump will wear out in time, that can also be repaired at a hot tub store cheap and fast.