well you'll eventually want to level ether (also I call her ether because her name is katakana (jap) is e-te-ru and I don't want to call her etel or something, lol, while the black mage is e-su-te-ru). just note that ether isn't really a tank (neither are priest warriors in general). they're more of a healer in a melee slot to cover areas where you can't afford to use a ranged spot for a healer.

hmm the only strategy I can think of that might suit your team might be: https://www.youtube.com/watch?v=KxqmivwbD-o
but if all else fails, just have to live with a not-so-perfect sukuha, but you can focus on getting a better team for future events. also, if you managed julian you'll probably want him as a 2nd soldier while you haven't cc'd phyllis.

also units you might want to add to your secondary army: mincosted alissa/christopher, calliope, bronze soldier, bronze bandit, bronze mage, spica and maurette (gold TP pirate in the future)
and you probably dont need niel (silver angel) because you already have nataku and eln. you can save that lvl 30 niel as a cc material since you need a cc'd angel for eln's AW in the future.

otherwise, you're pretty much on the right track.