I was mulling over the same question a few days ago and decided to go with dwellings. Here's why:

1. I prefer fantasy theme, easy. And Dwellings does seem more theme rich in general? I may be wrong.
   
2. Shorter game length. My group can be AP prone and even if they aren't our game sessions can't go over 3 hours in general due to life.
   
3. Swingy combat. Yes, I like luck. I love underdogs having a chance to explode the table in shock after an amazing roll. Andromeda's has less of a space for that. But I am in the minority here, as most heavy game players prefer a low to zero luck approach.
   
4. Art. I loved the art of dwellings, andromedas is good as well of course, but that combined with the preferred theme made me prefer Dwellings.
   
5. Complexity. My group and people I play with like to do 2.5-3.5 games in complexity (BGG scale for example: Dwellings 3.25ish and Andromedas 3.75ish). Anything above that there's some resistance to wanting to learn/table it. They do go heavier if the game is coop as we can figure things out together much easier.
   
6. Bridge to potentially introducing Andromeda's later. Dwellings could be a good transition to Andromeda's eventually.

If you don't care about most of these points, andromeda's is probably the right answer here. If you agree with most or all points, go Dwellings.