Welcome to Colorado.
A great area for someone who is wilderness savey is, South San Juan Wilderness Area. Get in 10 miles or so and you should have plenty of game. I'm not sure who rents horses in that area. As much as these outfits get to rent you horses , you'd be better off purchasing a couple and feed them and ride the regularly and you'll enjoy them that much more. Colorado sure is not Alaska but we have more Elk.
Try to put your tree stand in a tree with plenty of background cover, keep the prevailing winds for that time of the year to your face, and take care of those pesky squeaks and creaks your stand may have developed while sitting in the shed. A good treestand lube can be made by heating petroleum jelly until it reaches a liquid form. Some hunters have reported success by including a cover scent in this mixture before applying it to their stands.