Can a loop be used to improve water flow?

My house was originally plumbed in copper(based on remnants visible in unfinished area of basement). It is currently mostly CPVC. I suspect this is due to the acid well water.

I have 1 pair(hot/cold) of 3/4" CPVC line feeding over an unfinished ceiling to under a finished ceiling and then splitting to supply two inlaw suites. A 1/2" CPVC line then comes back along the outside wall to supply an outside faucet. It would be simple to cap the 1/2" line and do a tee from the 3/4" supply across the unfinished ceiling to improve flow to the outside faucet and cap off the old 1/2" line.

My question is: is there any drawback if I, instead, put a tee on the new 3/4" line going to the outside faucet and reverse the flow from the 1/2" line that previously supplied the outside faucet to feed the inlaw suites . This would increase total cold water flow into the inlaw suites (one 1/2"+one 3/4" line instead of one 3/4" line) but with water coming from two directions meaning the cold water pipes are in a loop as opposed to the one directional flow that is normal.

I suspect your flow problem is due to the 1/2" CPVC. The interior diameter of CPVC is approximately one size smaller than copper pipe of the same size. I realize this sounds weird, but what I mean is 1/2" CPVC is approximately the same inside as 3/8" copper. 3/4" CPVC is about equal to 1/2" copper. I think it is this size difference is what you need to compensate for.

The loop will increase the water flow.