When I had my "big" boat, a Chris 25 Sea Skiff, I installed a pair because I thought every boat of that size needed them. I'm trying to remember if I ever caught anything because of them. I trolled a lot of wire then, and I used side pole riggers and eleven foot wire line rods to spread the set. I think that long rods placed in flat line holders work equally as well as outriggers, at least in NJ where I did most of my fishing. You're certainly not going to be fishing marlin off shore with your rig.
Many ( maybe most) of the pelagics we caught back then were caught on flat lines pinned down against the transom. and running a wave or two back in the wake. I still occasionally use that technique in the fall when trying to locate little tunny to throw flies to, though I seldom troll anymore.
So...the outriggers looked good, but were essentially unused on that boat.