I have a 1968 gibson es335 that was very dark sounding so I put wolfetone legends in it which are alnico 2 and it brightened up the guitar considerably for the better. I have a 2003 gibson R7 that I fitted arcane triple clones in which are alnico 5 and that gave it extra grunt which I like.
I decided to swap them over as I was curious what alnico 2's would be like in the R7, I immediately knew when I plugged them both in that it was a bad idea, the R7 sounded brittle and weak with the legends and the 335 sounded shrill with the triple clones. Some pickups just work better with certain guitars, whether it is a naturally dark sounding guitar is a big factor I think.
I have a small-bodied semi-hollow that came with a SD 59 at the bridge. All bass and high-end and ultra-scooped mids - the construction de-emphasises the mids that the pickup was already light on. (Since replaced with a Bare Knuckles Mule - a much happier combo, for me). My experience is that lower output pickups work better in a semi, allowing more of the character to come through, but do watch for mid-scooping.
For a hollowbody I'd stay with potted pickups...unless you have a 100 foot long guitar cable and stand way far away from your amp. Then again Ted Nugent managed with his Byrdlands.
Semi-hollows you can go potted or unpotted. I have some Seth Lovers in my Sheraton and one Seth Lover in my AS93. Love what the unpotted aspect brings to the sound. It's hard to describe other than "airiness".
I think if you stick with the PAF-territory output you'll be fine.
Also, give a P90-in-a-humbucker a try for a semi-hollow. Great combination.