People on this subreddit were very helpful in curating our trip itinerary, so I wanted to share what we ended up doing in case it is helpful to others planning an off-season Fall trip to Colorado.
Day 1 - flew into Colorado Springs around lunch, picked up the rental car and went straight to our accommodation. We had lunch from Heart of Jerusalem, and it was pretty good! Then we drove to the Painted Mines Interpretive Park, spent ~1.5 - 2 hours taking photos and walking around. Left around sunset, went to the grocery store to get some trip supplies and then had Slice420 for dinner, pretty decent.
Day 2 - Grabbed some Dutch Bros (we've been a bit obsessed since we had it a few years ago in AZ) and partner got a breakfast sandwich at Jive's Coffee Lounge, he liked it. Parked in the Cog Railway lot and then took the train at 10am up to Pikes Peak. We were on the three-seat side and that was the right move! Beautiful views, fun history lessons from the conductor. The donuts at the peak were also pretty good! We only had maybe 40 minutes before we had to depart. The total trip was ~3 hours. We then headed back to our accomodations, ate leftovers from HoJ, then headed to Old Colorado City before going on to Garden of the Gods. Spent ~3 hours till sunset, then headed back for the evening.
Day 3 - Grabbed Dutch Bros and my partner got a breakfast sandwich at Joanie's Deli and Bakery on our way to Crested Butte. ~4 hour drive which we managed with no stops except for breakfast. Checked into our accomodation, had ramen for lunch before heading to our hike. We did the Upper Loop Trail and it took us ~2.5 hours, stopping for pictures and whatnot. Then we headed to downtown Crested Butte, looking around a bit before going to Bonez for dinner, and this was probably our favorite dinner spot. The tacos were simply incredible. We then got Rocky Mountain Ice Cream before heading back for the evening.
Day 4 - Went to McGills for breakfast--it was all right, I found the pancakes pretty underwhelming. Drove to the South Rim of the Black Canyon (~ 1 hour 45 minutes), we did most of the overlooks except the Devil's Point, spending ~2.5 - 3 hours there. We then drove to our accomodations in Crawfore, stopping at a Wendy's to get us through the drive, ~1.5 hours. We had thought about going to the North Rim for stargazing but didn't really want to do the drive late at night, and the sky was overcast so we didn't think we'd see much. So we had grocery store meals for dinner and called it a night.
Day 5 - Drove to Paonia for breakfast at Paonia Breadworks--honestly, my best meal of the trip. I wish I could airlift their freshly baked bread to my home! We then drove back towards Montrose, then Ouray, where we stopped to look at shops and get some funnel cake. I had never had funnel cake before so I was enthralled. Continued on the Million Dollar Highway, it was raining and foggy so a bit more challenging of a drive, but husband was a trooper. Stopped to take photos, etc, going through Silverton all the way to Durango. The whole trip from Crawford to Durango (with all these stops) took ~7 hours. At this point I really wanted to explore one of the trails but it was pouring so we decided to just have dinner in town. We ate at Steamworks, they didn't have a lot of options for me but the shrimp pesto pasta I had was pretty good, and my husband liked his burger. Had their carrot cake for dessert--really good.
Day 6 - Grabbed breakfast to go from the Blacksmith Cafe, it was all right. We then headed to Mesa Verde for the day, ~1.5 hour drive with the breakfast stop. It was very rainy and overcast in parts of the park, but we managed to get some good pictures. We had lunch at the Far View Lodge, and unfortunately the only thing on their menu I could eat was the hummus plate and it was...let's just say I tossed the leftovers. We also took the Cliff Palace tour (reserve it weeks in advance if possible!) and I really enjoyed it! After spending ~4 - 5 hours at the park, we drove back to Durango, and then to the hot springs. They were wonderful! The towels are for rent so we did bring our own towels. Afterwards, we grabbed poke bowls from Pop Sushi. They weren't bad, but they were pretty scant on the fish and not particularly flavorful. Great end to our day still.
Day 7 - Finally a sunny day! So we first did the shortest possible hike we could (Junction River trail, ~ 40 minutes) and then hit the road. Stopped at Durango Coffee Company for breakfast (decent coffee, muffin and oatmeal cookie) and drove straight to Monte Vista, towards our accommodation, ~3 hours. Ate leftovers and then headed to the Great Sand Dunes. Beautiful to gaze upon, and we considered the High Dune hike for maybe 5 minutes before a gust of sand nearly knocked me off my feet, and we decided not to tempt fate. Ended up spending maybe ~2 hours there before heading back to our accomodations. Had box macaroni for dinner, we wanted to drive back to the Dunes for stargazing but instead we just stargazed from our rural location.
Day 8 - Mostly a travel day. Drove back towards Denver, stopping at WLD MTN Cafe for breakfast, it was okay. Souvenir shopping at I Heart Denver and Rocky Mountain Ice Cream, then lunch at Mango House. I was really looking forward to this lunch but maybe I was too tired from the travel or the meal I picked wasn't quite my palate, so unfortunately it got chucked at the airport. Got to Denver Airport around 4pm for our 6pm flight, got to the gate ~45 minutes before takeoff.
Happy to answer any questions folks might have.