Solar Grid Booster Pump / Options

Can anyone provide assistance, recommendations for the following application?
I have an 27’ rnd ABG Pool, that has a ¾ hp pump/filter combo made by Sta-Rite. The original fittings that came with the skimmer/pump/filter have an final stepped down ID of 1”. It looks like I could easily cut the last step off and have an ID of 1 ¼”.
I have created a solar heating setup for the pool and I have approx 660 feet of ¾” tubing laid out horizontally, maybe 2’-3’ above the level of the pool pump with several (approx 42, 90 degree turns in it. My initial design has a 3 way Jandy Valve after the pump/filter and before the pool return that can divert from 0-100% of the water between the pool return and the solar collector. The Jandy Valve has a 1 1/2“ output to the pool return and a 1 ½” output bushing-ed down to a ¾” output that has a 90 degree fitting connected to a straight run of approx 20’ of ¾” tubing to the start of the solar grid.

My problem is I would like to produce a faster flow/more pressure thru the solar collector, then what I currently can get, even when I divert 100% of the pump output to the solar collector.

If I increase the ID of original fittings (Skimmer output->hose to pump->pump input ->>pump output (jandy valve)->hose to pool return) will that buy me anything?

If I increase the diameter of the Jandy valve output to the solar collector, and increase the diameter of the straight run of tubing before the solar grid, will that improve anything??
I cannot increase the size of the tubing in the grid itself.

My thought is the pool pump may not have enough power to push thru the many 90 degree bends in the collector, so if I add a booster pump right at the front of the solar grid will I be able to increase the throughput of the grid??

Can anyone recommend a pump suitable for this task? Ie. HP and or Manufactured?

Thanx in Advance