No-one has mentioned it yet? You will need the distance gun for WT, would seem otherwise, but they are way smart and will likely be running hard by the time that you realize they are there.
Mule Deer are dumber than dumb... like JT / Biden dumb. Stop moving when they raise their head from grazing... continue to close distance when they resume grazing.
Don't worry about cougars... it's rare to even see one. I live 100 yds from Ross Creek at the start of the incline to the Cypress hills... they are there...you just don't see them.
Rattlesnakes are only an issue in the fall and near the river... folks will swear they are a problem as far as Suffield... BS. They usually stay within about 5 miles of the winter den... which is always on the river ...IMO
Don't fret on a semi... you really are only going to get 1 shot that counts...then they'll be moving fast anyhow ( don't be 'That guy' who bangs off 1 aimed and 4 Hail Mary's). You will be doing a fair bit of walking... quads might as well have a bell or siren on them ( most Ranchers frown on them I've found)... you want to lug around a semi? Heavier and too much crap protruding IMO.
Just my opinion... that and a toonie will get you a coffee. But my Avatar? Great Grandfather came up from Texas in 1900 something... we've lived here a while. Mostly on the central / west side of the 'Hat... Elkwater is insanely cool... it's basically were the 'Foothills' reappear. Glaciers wiped out everything between South of the Hat to the foothills. Really cool anomaly Geographical wise... decent ski hill in Elkwater says it all.