I think your new route will work just fine...
McIntyre from CCBP to 32nd isn't too bad... there hasn't been a lot of truck traffic whenever I'm on it, though I don't ride it often just when I'm riding from my house in Applewood over to NTM or New Terrain. Also, there are pretty wide gravel "shoulders" along there, I've been known to duck off the pavement onto the dirt just to give a little space between me and traffic. If you're commuter has some tire clearance, that would work, no?
32nd from Golden to McIntyre isn't great with little to no shoulder and some blind curves, but it is better from McIntyre to Youngfield... it's more residential through there and I think there's a sidewalk for part of it. It is a fairly common bike route, and my sense is that folks who drive that road, drive it often and are pretty used to seeing bike traffic.
That new construction will likely have a corridor or through way there, I'd wager that your previous route (or something similar) will eventually open back up.
EDIT:
If you really want to stay off 32nd, you could duck through the Applewood West neighborhood, head south all the way to 20th, and then pick up 20th about where you used to pick up 32nd.
Also similar, is go through Applewood West to 26th, and at the end of 26th there's a foot bridge that goes over I-70 which would allow you to get east of I-70 and pick up 26th at Youngfield.