Need new pump and was my old 1.5 HP pool pump too big?

Hi -need new pump - Bought house 4 yrs ago - 16X32 In-ground pool - 4'shallow & 8'deep - Have Hayward Pro series sand filter Model S244T with 300lbs sand. Pump sits about 2 -3 ft above water line with discharge running up to pump house roof (8' high) to home made solar heater using 1.5" black PVC pipe (10-12 rows each 16' long). Pump sits 10' from skimmer and there is one skimmer and one deep end drain. The guy who put the pump in bought a Craftsman 1.5 HP and it has ran OK till now. He had it on a timer to go 15 min on and 15 min off for 14 hours. In reading posts I have seen where people with similar pools get by with 3/4 HP pumps. I am looking at the Hayward Max Flow II as it seems a good value. Can anyone tell me their opinion? 3/4 HP or 1 HP or 1.5 HP ??? Hayward or spend more for better? My electricity rates are only .06 kwh Thanks

If you want a two speed, which I would highly recommend, you would need to go with the SP2707X102 which is a 1 HP up rated pump (equivalent to a 3/4 HP full rated). The 3/4 HP up rated single speed would probably be big enough as well but the low speed is nice to have when not running solar. Also, the single speeds can be wired for either voltage while the two speeds are 230v.