The trip I really want to be doing and that i first thought about was LA-Vegas-Zion-Bryce-Moab-Denver. Which is fine for me. But, then I read about the roads to Denver and maybe snow
Well it's true there is a risk of snow heading to Denver but the same risk applies to Sequoia NP, Bryce canyon and other places. As we can't predict the weather it does make an itinerary harder to decide on when travelling off season. The good thing is the Colorado road crews are good at what they do as they get plenty of practice and have the right equipment and I-70 is a priority to keep the Nations traffic moving. I did lay out one possible itinerary for this trip earlier in the thread.

Vegas, and doing the loop, maybe to zion, bryce and moab and then getting back to Vegas. Do not want to be on the road all the time. Just enjoy as much as we can without overdoing it in 10 days.
This is where the 'balancing act' comes in, finding the ideal solution that matches your needs, too much or too little is different for everyone. Some like to stay in the same place for 2 or 3 days and others like to travel through and get an overview, possibly with future trips in mind. That's why I suggested you get the basics done and then we can get a better picture of what you want to do and help with the finer detail. Your first itinerary could work, but you could feel like you are pushing on too quickly as we touched on earlier in the thread.

From Vegas you could do something like this.
Vegas (1 night)
Zion. (2 nights)
Bryce canyon (1 night)
Capital Reef via UT scenic 12 (1 night)
Moab (Arches and Canyonlands) 2 nights
Grand canyon south rim (2 nights)
Vegas (1 night)

You could also consider heading from Vegas through Death valley to Yosemite NP and Sequoia NP and possibly include the Grand canyon but you would run a higher risk of weather disruption and possibly road closures in the Sierra's.