Thank you Kirakira for your thoughtful response. Yeah I will do just that, I made a character on each of the servers in question and I am kinda feeling them out just getting to like level 20 on each one.
So far Mateus seems to be a really good fit. It has plenty of people chillin in Ul'dah having fun, and the economy seems better for selling, which makes sense because Balmung has been closed to new players for quite some time.
I had a lot of hope for Diablos because the name is badass and they have preferred status, but its very nearly empty compared to Bal/Mat. So my fear is, I put in all the effort to raise an omnicrafter and nobody really wants or needs the things I can make. I guess one factor is housing: I am sure its near impossible to get a house on Bal/Mat but I am so far behind on content I can hardly even fathom something like owning a house anyway. I will be happy with an apartment I can put some aquariums in.
My character isn't really a multi-job concept: she is JUST a knight, so I really only plan to level PLD/DRK and maybe DRG just to have a damage dealer but I don't actually like playing dps.