After skimming over the profiles, I'm thinking either Valsil or Elara. I imagine Elara would end up growing the most from being in a leader position but I also see some potential in her, some radical moves and unorthodox methods at the moment; the Padawans and younger Knights will probably want her passion. Valsil on the other hand has a profound dedication to the Jedi Code. I can see other Knights wishing to have that master-like dedication guiding them.

EDIT: My real choice here was Traest Krey’lis, he has that militant knowledge that we all need. But you I figured the Jedi senior officer needed to be a Jedi.