Austin to Vegas and Everything between in 2 weeks

We are taking a road trip to Vega in Sep-Oct time frame and want to take the most scenic route available. We have 2 weeks, and we want to spend 4-5 days at least in the colorado/utah area. We are going to spend a couple days in Silverton tentatively for the atv tours, but want to take all the scenic highways as well. I am assuming US 550 is a must, based on the comments I have read online.
We want to see majestic mountains at high elevations along the way, spend 1 day at the Grand Canyon, and then last few days in Vegas. If anyone has made this tip and has scenic drive suggestions, I am in the process of trying map it out and would appreciate any suggestions.

As far as scenic routes through CO and seeing majestic mountains goes, you can't do better than to start off by driving the Trail Ridge Road through Rocky Mountain National Park. This is the highest paved road in the US, traversing the mountains at some thirteen or fourteen thousand feet. At that elevation snow and blizzards come at any time of the year, so check, before you go. But hey! even if it is closed up the top, if you drive as far as you can, you will still get magnificent views and scenery.

Yes, 550 is one of some folk's favourite. But then, 50, 160, and many others are spectacular as well. Almost any road you choose, west of I-25 is a scenic and mountainous route, and worth driving - IMHO.

Lifey

This could be an eminently relaxing, scenic, and thoroughly enjoyable trip of you have two weeks for just getting to Las Vegas. It could even be done as a loop back to Austin over two weeks, but the pace would be a bit faster with less time available for Las Vegas. What I'd suggest you do (assuming a one-way trip) is to initially head up to Walsenburg CO via a collection of US and state highways heading northwest through Stillwater, Lubbock, Amarillo and Raton. From Walsenburg take US-160 over Wolf Creek Pass. This is a high mountain pass, reaching over 11,000 feet and is spectacular in sections. US-160 will eventually bring you to Durango. From there, the Million Dollar Highway (US-550) will take you up to Silverton and back. Returning to Durango puts you in shape for the next portion of your trip, the Four Corners area.

From Durango hop back on US-160 and head west to Mesa Verde, Four Corners, and Monument Valley before heading north on US-191. Now, if time permits, you can head up to Arches National Park, but the objective here is to take UT-95/UT-24/UT-12 across the heart of the state through Canyonlands National Park, Capitol Reef National Park, and Bryce Canyon National Park to Zion National Park. From there, I think I'd try to include the Grand Canyon before you end in Las Vegas by doubling back a bit through Page to Cameroon which would set you up to take the Rim Road along the south rim of the Canyon to Grand Canyon village, exiting to the south and then head to Las Vegas. If you still want a bit of road adventure, you can take the last, longest remaining bit of the old Route 66 blacktop from Seligman through Peach Springs to Kingman.

AZBuck

Yes, a one way would be wonderful, but unfortunately...work and not enough money to retire yet means I have to return to hot, dusty, humid, horrible Texas.
Anyway, it is going to be a round trip, so since that is the case, which part would you drop to make the timeline work?
I have been to the Grand Canyon many times years and years ago as a kid, but have never seen the Rockies, so that is the main part we want the most of.
Even a simple stop for a few hours at the Grand Canyon on the way to Vegas would be viable, but if it is too far out of the way, dropping the Grand Canyon is on the plate as CO/UT sight seeing then couple days in Vegas are the musts for this trip.

As I noted in my original response, you can still do this trip comfortably as a complete loop back to Austin. The key will be to simply keep in mind that you have to leave Las Vegas with three full days in hand, so that you can still see a few sights on the way home and arrive home with time to unpack and relax, and get a good night's sleep, before heading back to work the next morning. What would I drop, well as I suggested, I wouldn't try to get too far north in Colorado, skipping Rocky Mountain National Park in favor of using US-160 to cross the Rockies in southern Colorado. I'd also drop trying to get to Arches National Park and rather visit the arches that are accessible off US-191 in southern Utah on your way up to UT-95/24/12. Finally, you can drop the visit to the Grand Canyon and just head into Vegas from Zion. On the way home, some easily accessible stops would be Meteor Crater, Petrified Forest National Park, Petroglyph National Monument, and if you're of a certain age, the Buddy Holly Museum in Lubbock.

AZBuck