Unlikely to be a problem with a normal unicycle hub, and to be honest it’s very rare for spokes to be over tensioned - if you’re not used to building wheels the chances are you’ll think they’re too tight well before they actually are. Most new wheelbuilders undertension their wheels (the very first set of wheels I ever built I had to stop at the roadside to tighten the nipples by hand as they were so loose they were coming undone as I rode!)
I’m clearly missing something here - why does the longer spoke make it less obvious that the spokes are too tight? I’d think it was maybe actually a problem with the larger rim taking less tension, but you also mention nipples snapping…