The actors have aged which is why the idea of a good animated series is appealing.

I wouldn't mind other stories set in the Firefly universe either, such as Earth's abandonment or non-core-planet drama or a space opera ala The Expanse, etc. It's a potentially rich setting which has barely been tapped.

Forget the crew of the Firefly and move beyond them.

 

I guess if there were to be a reboot I would prefer it be animated. Its hard to imagine anyone else coming close to recreate the magic that was Firefly though.