I have some expertise on this I made perhaps the first full non mod of exile lands map pre siptah before maps were even supported, it took a lot of time, and wasn’t feature rich at all.

I did it across 2 weeks pretty much 11 hrs a day sadly it’s no longer functional and I don’t have the time (or will for that matter) to update it.

Mind you if a solo developer can make a functional at the time map across 2-3 weeks pre tool support a small team should be able to crack out something decent in about the same time.

Now more onto the meat of it would a new official map be good for exiles? depends, we don’t need a DLC split map, it would ideally be a map maybe people could transfer to within a cluster, and ideally you would want the map to be free even if a DLC gated some of the cosmetic content to cover costs ?