Winter is my favorite time, I hope you get snow. Personally I've never been shut out by a snowstorm, but I would advise caution on the slickrock, especially near cliffs, if it is snowy and icy. What can be easily doable on dry, grippy rock can quickly become absolutely treacherous on snow - just becasue the trail looks like it goes that way may not mean it is safe in those conditions. Of course it totally depends what trails you are on (I'm thinking outside of the super-popular spots). Also, nothing to be overly scared about for someone with hiking experience, just common sense really.
Roads - stay on the main roads/tracks unless you really know what you are doing. 4WD out there is not 'anyone can get through if they have a 4WD', even in the summer. I don't know what it is like now, but 10 years ago winter could be quite empty outside of the hotspots (like the ones you mentioned). If you want you should be able to find yourself quite alone.
My experience has been that like Denver, most storms move through fairly quickly, so even if you are shut out for a day or two, the scenery as the storm clears and just after will more than make up for it. More than make up for it!
Actually, although the chances of seeing a mountain lion are next to nil, if you do have fresh snow, the chances of seeing tracks is not so small (if you get out into the back county a bit) and you get an appreciation for just how much wildlife is really out there. I have actually seen a mountain lion in Canyonlands NP , but in 15 years of going I have not even talked to a ranger who had. I've seen numerous tracks in the winter (in fresh snow) and the Rangers in Canyonlands see lots of evidence (animal parts, tracks, scat etc..) so they are really, really good at avoiding humans.
Red rocks, fresh white snow and deep blue skies - OMG, it's just about perfect. My favorite place in the winter. My kids are still a bit young to go in the depths of winter, but I'll be taking them camping over future Christmas holidays for sure.
lastly some personal thoughts on trying to photograph the area:
I would advise getting away from the usual spots. There are great shots to be had all over and they will be much more original and I think in the end, more personal. Sure do the icons if you wish, but then (IMO) you just end up comparing them with others that you have seen where the photog spent years going to the spot to get that shot. Personally I've never photographed those spots and don't intend to, but that's just me. I guess what I'm saying is get out and explore as well as going to some of the spots you have read about - I think it will be worth your time. I guess it's also a very personal thing, but I figure if you've done quite a bit of hiking and climbing alone, you may be like me and will enjoy the off-the-beat places more.