For a 2 to 3 hour visit, Amelia or Spello?

We have spent quite a bit of time in Umbria, and I have never heard of Amelia. When I looked on Tripadvisor for things to do there, most of what came up was nearby, not in the town. If you go to Spello, you can very easily include Montefalco and Bevagna, all lovely hill towns, and very close to each other. You could see 2, or even all 3 in 3 hours. You might also consider Spoleto, which has more of interest than any of them.
Though you didn’t ask, I’m going to give you my opinion that I can’t imagine what you would do in Civita for a couple of hours. It is definitely not a “great” hill town. Any or all of the aforementioned would be much better choices.

We've not been to Amelia, but we did visit Spello as a day-trip from elsewhere. We were there about six hours, including lunch (and walking from the car park), and thought it entirely fine with some attractive gates/walls and pretty streets; but not much "wow" until the views when you get to the top, which involves a bit of a climb. Although I'm sure you could see the highlights in much less time than us.

I don't recall it as the most interesting hill town, at least compared to, for example, Gubbio. We parked at the bottom and then walking up to the scenic parts. So three hours might be more practical than two if you're having luncheon.

Spello. We always parked at the lot at the top of the town. There are several lots on the side too. We love this town and spent two weeks there. Perfect location near other charming towns as well as Assisi and Perugia.

Had a fantastic meal at Il Pinturicchio in beautiful Spello in January. Just delicious and lovely. Most people around us were speaking Italian, too and clearly appreciating their meals. So if you don't eat in or near Civita, call ahead to Spello for a reservation

Have you considered going to beautiful Orvieto?

I enjoyed my day trip to Spello when staying in Assisi.

Enjoy your trip!

Edited to add...
I also had a truly delicious lunch at Il Pinturicchio while in Spello 😋

Hi DB,
Been to Amelia, if only for a few minutes. It is off the beaten path. Our masseuse @ the aforementioned splurge Abbazia S. Pietro en valle was from Amelia and when she later doubled as our taxi transfer, she deliberately took us through her remote home village. The vibe there seemed arty, authentic, quiet and small. I'm guessing that there wazzam (was and still are) but 2 or 3 restaurants there.
By contrast, the vibe at Spello seemed more staid. It is a gentrified, larger, steeper kind of place, with a wider selection of eateries. It too was unexpectedly quiet. There were more tourists at Spello, as well as better overall views of the surrounding countryside. Betcha that whatever you'd spend on a meal in Amelia, you'd spend more in Spello for the same.
Surely, either place would be a wonderful visit. Good luck!
I am done. The end.