If you can find out what cut the roast is it would help us in giving advice. The description you give means that it might be a neck roast and, if so, lot would depend on the age and condition of the deer. My experience has been that the neck meat from does 2-1/2 years and less or bucks 1-1/2 years and less is generally very tender but I hunt in pretty rich farmland and a deer that's working a lot harder for its meals may be a lot tougher.
In any case, without seeing the cut my best guess would be that I would roll the slab and tie it into a roast and then smoke cook it.
Personally, I'd shoot for a smoker temp of 200 degrees and be happy with less. My experience has been that you don't need to worry about drying it out from time at low temperature as much as drying the outer parts at too high a temperature. It I've got a roast I'll often quickly brown it in a screaming hot iron skillet before smoking or roasting it in order to add another layer of flavor. Even in the oven I don't go much over 200 degrees if I've browned it.
We process a fair number of deer. As we know how the deer are handled from the time they're down until they are in the freezer I'm not as concerned with bacteria as I might be otherwise. Most venison cuts are rare at around 125 degrees internal and medium rare at about 130-135 degrees. If you are at all unsure of how the critter was handled along the way you might want to go to the temperatures recommended by most cooperative extension folks of 145 for whole muscle meat and 160 for chopped or burger meat.
If you're within driving distance of me and want more venison to practice with shoot me a PM. I've got two freezers with a lot of venison in them, there's a lot deer around and the season is coming up fast. I'd be glad to give you some.