Proper Sizing for Replacement Pool Pump and Filter

We have an inground rectangular pool (35,000 gal) and need to replace our old pool filter and pump. We just moved into the house last year and battled algae all summer long, suspecting that our current old filter setup doesn’t provide enough throughput for our size pool. We currently have two 1.5" input lines (one from floor drain, other from 2x skimmers) going into the 1.5HP Hayward Superpump and one 1.5" return line to two sidewall returns in the pool (I’ve attached a rough sketch diagram). The current Hayward S-240 sand filter is rated for 50GPM. I’m in the process of running new lines to my two skimmers to repair a suspected leak in one of them, so I will end up with three dedicated 1.5" input lines coming to my pump. For our new pool equipment, we definitely want to go with a better sand filter that can handle more GPM. I’m a bit unsure on the pump (ex. can i combine the three 1.5" inputs into a larger pump with a 2" input? Would this not be an option because it could damage my single 1.5" return line? Is there a setup that you would recommend for our situation?

We’d recommend the following pump and filter for your pool. The filter can handle 70 gpm.

Click Here to View the Waterco Infinium ECO V-150 1.65HP Variable Speed Pump

Click Here to View the Waterway Carefree 26" Sand Filter