I’m a fan of large water volumes and smaller bio loads. A lot of the better reef tanks you see have a small fish count or large ratio of water/fish for a reason. This is especially true for SPS and mixed reef. Also, when thinking of fish count think about the adult size. As you mentioned you had a problem in the past. Large amounts of waste means disease can spread easily. I dumped a powder blue covered in ich into a 150 was healed with no spots with a few weeks. Also, he fights with a yellow tang and each one gets gashed tiny infection and heals within a week. They’ve both been thriving together for over a year.
Other people love the large fish loads. If you do, I’d recommend a larger volume. I have two sumps. Drain through the wall into 100 gallon Rubbermaid, back into the under tank sump and return.
Bottom line - less fish, cleaner water, less algae problems, less fish disease problems. If you do keep a high volume it will be imperative to do your water changes on time changing out filter socks, etc.