Even if the snowcat is running it's not backcountry...
The snowcat running up Tucker mtn is very much inbounds and avy controlled. Which is a good thing. If it's not open generally that means conditions are still thin. Any other backcountry you want to do is going to require some high altitude hiking, long skins, or a snowmobile to get you back there. It's also going to be full on avalanche country with the sketchiest snowpack in North America. If you don't know what you are doing and are not properly equiped, someone stands a good chance of getting buried. A very seasoned backcountry skier
got buried last weekend. They recovered him because he had a beacon on and his partners knew how to use their beacons and dig effectively. He was still under 2+ meters of snow and buy all indications busted up. Broken bones etc. Last I saw he's on a ventilator in a coma. Probably going to recover but is done for the season. Anywhere you go snowboarding outside of the resort requires knowledge of how to assess and travel in avalanche terrain. I don't get the feeling you have much experience in this.
So you could look at taking a level I avy course with your and your buds, everyone invest in a beacon, shovel, probe, snowshoes, and/or splitboards. If you really want to go bc I highly recommend taking the course. It's very rewarding once you know how assess the dangers. It's still dangerous, especially right after the class, but you have enough knowledge to make sound decisions as long as you use it.
Second option. Pay for a snowcat operation. Chicago Ridge Snowcats
runs out of Cooper (not Copper) mtn outside of Leadville. They take you in the terrain that the 10th mountain division trained in for WWII. Not super steep, but I have heard really good reviews about the riding. Powder heaven when it's on. Cool burnt out old forests, some really neat stuff.
Sorry if I sound a little harsh early on, but I need to make the point that it is deadly serious if you don't have the education and knowledge about backcountry. I've seen 3 bodies pulled out of the bc that were before the burial top notch expert riders. If you get caught it's serious. Chances are you'll die in the burial. If you don't die and don't have the right equipment there is no way your buds can find you or you find your buddy. The second you go for help you are going to a funeral later.
So that kind of runs the gambit. If you are looking for inbounds "backcountry" there might be a few more options such as Vail. So let us know...