Morgan
We will be heading to Breckenridge on Thursday the 19th and would love to see people! Events don't start until Friday the 20th though.
Breckenridge is at over 9,000' elevation. We recommend drinking plenty of water (and watch the drinking somewhat) to avoid altitude sickness. It can be helpful to acclimate in the Denver area (5,280') before making the drive if you have the time. Oxygen canisters can also be helpful in desperate times.
Colorado is known for being sunny a majority of the year but there is the occasional afternoon rainstorm. Once the sun sets it can also get chilly at altitude. Basically - no idea.
On its day, I-70 can be quite a pain. This time of year, the traffic is usually dispersed but if there is construction or an accident, it can sometimes double the drive - or more. There are a few side routes that you can take. I would just check the maps before leaving and give yourself plenty of time if flying home.
Yes.