The Reason to 7* and gear Phoenix beyond Thrawn

Get Thrawn

I really think anyone could survive a life without a Thrawn in his roster. At least I do.

Easy GW

GWs already are easy with a rebel team, a resistance team or even a Sith team under Nihilus lead.

Beat LS Hard Node 9 A-D easily

Same as above plus Jedis minus Siths of course.

Use Ezra and Kanan for other Legendaries (I would imagine whole Pheonix would handily defeat EP as well)

I don't think that Yoda is that mandatory anymore since he's still the crappiest legendary around. Anyway Jedis are damn common and finding 5 of them is a cakewalk witout a single Phoenix.

Actually Ezra alone is worth being farmed and geared to make Jedis even better. Kanan isn't performing well as a tank.

Their ships once farmable (who knows when) look to be great

Not much relevant since they're not farmable yet.

They are fun and thats all that matters in the game

True. Same as Ewoks.
You can enjoy a lot playing them but there's no point in playing Phoenix in raids at the moment, which is a big NO for me at the moment.