I think there’d be too many expectations from a lot of people that’d potentially ruin the films whichever way they go.
I’d be all in for more personal stories set during the Clone War, I think it’d really do womders for that time period. We get some of it from the TV shows, but nothing actually good.
But yeah if they want to stay away from the main saga at all costs I think the old republic era is definitely the most logical pick. I really don’t want it to be a Jedi story though, I think it’d be cool to see more Rogue One-like films.