I like to hunt both, I would find an area where you have some diversity in the landscape, specifically elevation. The biggest issue with open country elk is that most of the time it's hotter in the open country so elk are much less active and normally stop moving earlier and don't start until later. You can also find open country above treeline, which is kind of the best of both worlds, high country normally has the lowest densities which sometimes means more spot and stalk. I've found that low country, especially around private, has the biggest herds, which typically means more rut action more often.
The low country can be fun, depending on the state you may have to deal with rattlesnakes and scorpions in the low country. Also, more heat means having a better plan for meat care. I don't stress at all about meat care in the high country or timber country because you can normally find a tree to hang meat in the shade, you also have good thermals up higher which can not only cool meat but helps when getting close to animals.
I think in general, the most elk live in the middle elevation timber and it is the best by far if you want to call elk and get close to them. It's very hard to get into most peoples effective range in open country. Unless you find a bedded bull by himself it's much harder to spot and stalk elk than deer. Elk run in herds so you have a dozen or more sets of eyes, ears and noses that you have to fool.
The biggest problem with picking one is that if the unit you chose only has elevation between 5-6K feet and elk are not active or rutting you cannot change things up much. Typically, I go high early in the season to 7-8K+, and hunt timber when the rut picks up. If I'm struggling in the timber with no activity, I will move down to the lower country and glass for elk.
As far as predators, the only thing I would worry about is grizzly's, every other predator is a non-issue 99.9% of the time. If you're planning on hunting grizzly country just have a good plan. Honestly if you're not familiar with back country meat care and have never packed out an elk I probably wouldn't plan my first elk hunt in grizzly country. There are a lot of great hunting areas that don't have grizzly