You have come up with a nice plan there Linoy ! We can certainly help and make suggestions and answer specific questions, but as for your day to day planning and routes, that is something you should continue to work on so that you make it your trip as this is what seperates a roadtrip from a 'Fly-drive' type holiday where others pick for you. Don't forget the planning is part of the fun !

Some thoughts so far; You can certainly make it out to Guadalupe mountains / Carlsbad caverns in a day from Dallas and possibly tour the cave that afternoon/evening. You then stay in the area and visit the mountains next day and then you could stay another night in the area, or start making your way towards your next stop. I would consider driving to Monument valley after Lake Powell and on the way to the Grand canyon south rim and not next up from Carlsbad. It will make it an easier option to drive through the mountains to Arches NP. More on that in a minute. So after visiting Carlsbad I would look at Albuquerque or Santa Fe to overnight.

From Santa Fe /Albu you could then head to Mesa Verde NP via Pagosa Springs on US160. Cortez is the nearest town although there are other options. Nearby Durango is home to the Durango/Silverton railway and is a wonderful ride up to this old western town. So you could spend a couple of nights here as the tours in Mesa Verde do take up time.

To get to Arches [Moab] you could take the spectacular drive up the 'Million dollar Highway' [US550] through Silverton and Ouray and take US50 towards Grand junction. Nearby you will find Colorado National Monument with wonderful views from the rim drive through the tunnels. You could make it Moab or stay in Grand junction/Fruita the night. As you make your way to Moab, [A good base for exploring Arches and Canyonlands NP's] take exit 214 onto UT128. It's a lovely detour through Castle valley, following the river through red rocks and it hardly costs any time over UT191. You will really need at least another couple of nights here to explore the parks.

Next up you will go back to I70 for a short while and then take UT24 to Hanksville and onto Capitol Reef NP. There are lodging options in Torrey that a more budget friendly, or there are a couple of options nearer the park, one being a very nice Best Western resort. You will have time to explore areas of Capitol Reef the day you arrive and before you depart the following day.

Next up, make your way to Bryce canyon via Utah scenic 12. Tropic has lodging but there are some closer, Ruby's Inn the nearest and very popular. After visiting the park you could then make your way to the wonderful town of Springdale which is located right by the entrance to Zion NP. I would recommend 2 nights here to explore the park.

I would think 2 or 3 nights in the Page/ Lake Powell area to explore the things on your list, although the Wave is very limited in how many people can visit. You should look into the detail. You could include a visit to the North rim of the Grand canyon on the way to Page where there are lodging options at Jacob Lake [good value cabins available] or Marble canyon.

After exploring the area you could head to Monument valley for the day and spend the night in Kayenta or at the interesting Cameron Trading post which is in a good location for entering the south rim. Spend another couple of nights in the area, perhaps Flagstaff for the following night. After this it's off to Vegas with a possible detour to the old route 66 towns of Seligman and Kingman and a stop off at the Hoover Dam. After a couple of days in Vegas you could make your way to LA via either Death valley or the Mojave National preserve.

Remember these are only suggestions for you to work with so see what you think and 'tweak' it to your tastes and let us know what you come up with.