From this weeks arches info- you may not have pets on hiking trails, overlooks, or in backcountry even in carriers. You may walk them along roads and in parking lot - but WAY TOO HOT to leave them in a car. Moab has kennels with boarding services.

Yes, the roads are well marked with names of attractions and junctions with side roads to attractions. However, as is common in national parks, I do not remember seeing highway route number signs in the park. Please use the park map and or a gps navigation system to track where you are and where you wish to go. I found the roads to be very well marked as they are in Yellowstone and Grand Teton national parks where I work but visitors often complain because they don’t take the junction signs at their face value and as very accurate and all the signage needed.

Hi, April is the best time for hiking in Utah. Don't spend too this time for a long drive, better for hiking itself. Nor as far from Grand Junction you can explore Gunnison Canyon NP and Curecanti area. Then you can get impression drive through Million dollars Hwy to Mesa Verde NP (all mountain passes still closed on April). The other way - to Arches NP (and Castle valley) with a lot of trails. It will take minimum 2-3 days. Then huge Canyonlands NP - several districts of this park provides trails for a lot of days. Or can continue to the South - Gods valley near Bluff, or to the West from White Mesa to Natural Bridges, and then follow HWy 95 to Colorado river and more far.