You bring up many valid points.

I'm very limited with my current setup as there is no backwash. Vacuum is done with a Ray-vac (pressure return).

Picture a box mounted next to the pool with 2 canister drums. One is the skimmer, pulling water from the surface, and the 2nd drum is from the main return at the bottom of the pool. This drum has a sealed lid, thus the pump draws evenly from both sources through the cartridges.

I have to rinse the cartridges almost every day to preserve proper flow to keep the water clear. I'm currently using Softswim, which is part of the problem, but my family seems to enjoy it and are hesitent to switch to chlorine. My wallet says please do...

I'll try to post some pics in the next couple of days so I can get some better feedback.

I grew up with a sand filter, so it's good for me.

DE seems like more work, but maybe not as much day to day as my current combo.

I know 2 people using biguanide products with sand filters and they're very happy.