Just to confirm, solar heating works best at higher flow rates. You get more heat in the pool by heating a lot of water only a few degrees (at higher flow rates) than heating a little water many degrees (at low flow rates). Ideally you want the pipe to feel cool to the touch and only want the water temp to rise a few degrees through your solar system.
Certainly you will want to split all that up into multiple parallel paths, I am not sure that 4 is enough, but would certainly help over a single loop.
BTW, the house I bought had 2500 feet of 1" pipe in 8 different loops for my 18k pool. This was about 200 sqft of heating if it would have been laid out nicely. It was hardly adequate. I now have 500 sqft of true solar panels which works great. Solar heating is all about area of sun exposure and flow rate.