Nick,
Yellow and sunflower family you get all kinds that are so similar there is a name for just studying that family, That is a crazy thick patch of veg, Mules Ear seems right to me too, they open up in to nice flowers.
The purple flowers photo above I'm going to go with Moss campion,
Silene acaulis, Pink family, which I first finally photographed near the Pfeifferhorn last summer (I should do a report here one of these days).
I love the SW Colorado Wildflowers site mentioned above, several neighboring states sites can be helpful too. Here is a list of online sites and resources I frequent while trying to identify flowers which I try to keep updated over on the Expedition Utah forum (let me know of any dead links), includes those already mentioned.
Arches NP wildflower guide online
http://www.nps.gov/archive/arch/flowers/flowerhome.htm
Capitol Reef Wildflower PDF [also a great book]
http://www.xmission.com/~nelsonb/capitol_reef_web3.pdf
Desert Plants Of Utah PDF, Utah State University, Berniece A. Andersen
http://www.ut.nrcs.usda.gov/despub.pdf
Digital Atlas of the Vascular Plants of Utah
http://earth.gis.usu.edu/plants/
Montana Plant Life
http://montana.plant-life.org/index.html
Natures Medicine Chest (edibility and medicinal uses)
http://livingwithbasics.com/naturesmedicinechest/nmc_index.html
Northern Arizona Flora
http://www.nazflora.org/index.html
Southwest Environmental Information Network (SEInet)
http://swbiodiversity.org/seinet/index.php
S.W. Colorado Wildflowers (nice resource, as many species are endimic to both states)
http://www.swcoloradowildflowers.com/index.htm
USFS Wildflower viewing areas w/ maps. Intermountain Region
http://www.fs.fed.us/wildflowers/viewing/region.php?sort=forest&arearegion=Intermountain
USU Range Plants, Alphabetical list Index by Common Names
http://extension.usu.edu/rangeplants/htm/alphabetical-index-by-common-name
Utah DNR partial list of rare Utah plants
http://dwrcdc.nr.utah.gov/rsgis2/Search/SearchSelection.asp?Group=PLANT&Species=PLANT
Utah Native Plant Society
http://www.unps.org/index.html
Utah Rare Plant Guide
http://www.utahrareplants.org/rpg_species.html
Utah State Noxious Weeds List
http://plants.usda.gov/java/noxious?rptType=State&statefips=49
Utah Valley University, Herbarium: searchable Online Specimen Catalog
http://herbarium.uvu.edu/virtual/
Utah Wildflowers; B Nelson
http://www.xmission.com/~nelsonb/wildflower.htm#family
Wasatch Bloomers; Wasatch Front Wildflowers
http://www.wasatchaudubon.org/flowers/index.htm
Weeds and Wildflowers of Utah index
http://www.rootcellar.us/wildflowers/contentt.htm
Wild Utah Plants index (great detailed photos of wildflowers)
http://www.wildutah.us/index_plant.html
Wild Edible and Medicinal Plants
https://keys2liberty.wordpress.com/
Oh and one I need to add that I use often is the USDA Plants profiles
http://plants.usda.gov/java/
If you think you know or might guess at a family or genus, use the common and scientific name search in the upper left corner and browse through the genus found under that family. Or in a google search with "USDA"