I think RMNP is a great place to photograph a wide variety of wildlife, but I must admit I've not been there in March/April. The elk will have shed their antlers, as well as the Mule Deer. The Moose have already shed. Of course, you can still enjoy photographing them - and get some good images to boot - even when they don't have their antlers.
There should be lots of songbirds at that time. There are always colorful Magpies about. Ground squirrels will most likely still be in hibernation. The park has a decent population of Wild Turkeys on the east side, and they should be in their mating season at that time, so you may be able to capture some strutting displays if you're patient and lucky.
"Your" and "you're" are different words with completely different meanings - please use the correct one.
"They're", "their", and "there" are different words with completely different meanings - please use the correct one.
"Fare" and "fair" are different words with completely different meanings - please use the correct one. The proper expression is "moot point", NOT "mute point".