I have had a little change in heart for now. I do believe that I will eventually get a HOB overflow, just for the compact design and the ability to have a wider skimming area, and the ability to have a small volume of water inside the overflow which will allow me to dose before the sump and potentially add easy-access media bags that I can more easily monitor.
For now, the goal is to either replace my AC50 with a Seachem Tidal 75, or get a Seachem tidal 35 to go alongside the AC50 to add cheap surface skimming and additional basket space. I would love to be able to dedicate one filter to Purigen and Chemipure elite and the other to carbon and filter floss. Probably will put the purigen and Chemipure in the Tidal as its the one that will be skimming the oils off the surface.