That LSS is a nice looking rifle. I have both a 270 WSM (TIKKA T3 Lite) and a 300 win mag (Model 70). I too hunt mostly deer with them. My thoughts:
The R3 (sims) pads definitely make a huge difference. the LSS may come with one, not sure. if not, it's easy to install one yourself. Regardless of caliber, I'd put one on.
I don't think the reduced recoil loads are a viable option. If recoil is that big an issue, just get a .308 and limit your shooting range while not having to pack around a bigger rifle.
I shoot the 150 grain bullets out of my .300 -Hornady interbonds- and it kicks, but not as bad as you might think. I originally had the boss muzzle break on it and could not handle the noise, so I switched to the conventional recoil boss. It's definitely doable to get used to it if you shoot some.
In the 270 WSM, I shoot the 140 grain interbonds. The rifle is about two full pounds lighter than the .300, and the bullets leave the muzzle at a similar velocity as the 150 grain .300s. The .270 kicks slightly less out of the considerably lighter rifle, with similar weight bullets. I would think that in equal weight rifles, felt recoil would be noticeably less in the .270 WSM.
Personally, I'm going to shoot the lighter .270 WSM for everything except the big stuff now that I have it. Like you stated, I could also use it for elk, and might, but what's the fun in only having one rifle? Good luck with your choice, but there are lot's of options out there to find the caliber you really want.
WH