FWIW...the Wolverine has a lower gear ratio stock vs. stock compared to the viking. This obviously gives it the edge in low speed torque and pulling ability, while being slightly more reliable. However, if you wanted to get the viking, you could just slug the wet clutch, throw in a modified sheave, and call it good. It would then have the edge over a stock wolverine. BUT, you can do the same work to the wolverine, so it's really about whether you want to leave the machine stock or not. The Viking is clearly more utilitarian, but the wolverine has slightly more engine power, and the edge on the gear ratio, making it a better puller when still stock IMO.
You mention pulling a boat, hauling firewood, etc. The only downfall with the wolverine is the springs...there have been a handful of people, myself included, whose springs sagged badly after a short amount of riding(100 miles or so). So loading up the bed would not fair too well without some correction-like a lift kit, replacement springs, etc. The vikings had this same problem, only it was much more wide spread than we have seen here so far. To fix it easily, people removed the stock springs and replaced them with stock "Viking VI" springs, which were much stiffer.
There are several members on here who have plow setups, no real complaints that I have heard as of yet. Again the only limiter would be the springs, if you happened to be one of the few who had issues like me. As for trail riding, this one is truly a no brainer, the viking cannot even compare to the wolverine in comfort or capability. At least, not stock vs. stock anyway.
Just my 2cents.
FTM
EDIT: I'm an idiot. Just realized after rereading your original post that you were considering a used Rhino. Other members mentioned the Viking. I will let someone else compare merits with the rhino as I have less experience with them. Now you know a bit about vikings LOL.