Rounding out odd stat's would probably be my first goal.
I'd worry about Dwarven fortitude a little later as when you pick up the periapt. (aside: what is your bonus action strategy for when you use your action to Dodge?) I'd also put off warcaster as you can hold a shield and cast spells and cantrips with your other hand (holidng an arcan focus or component bag) just fine, drawing a weapon for attacks and Booming Blade.
Shieldmaster is useful at any level, though I'm not sure I'd put it above ASIs.
So if it were me getting Cha to 16 is a first, and getting it to 18 second would probably be my second priority. the others depend on whats happening in game. If I have the periapt, DF, if I have the Thrower Warcaster, if neither Shield Master.