Picking out a creature that's supposed to be a personal statement about my character, and which will heavily influence said characters visuals, and hold some sway over their powers is pretty stifling, yeah.
As far as 2e goes, spirit shape determines: 1) Your first "other" shape, 2) DBT (If you choose to take it), 3) Your iconic anima. Technically also the Tell, but I think we all agree that limiting those to spirit shape is pretty dumb. As for the tats, well, I think they're a cool visual (YMMV), but you can hide them (again, needing a Charm to do so is really dumb.) All told, if it still bugs you, then sure, you can rule that at your table, Lunars don't need them. I'm just explaining part of the rationale behind why they're sticking around.
What is TAW?
Terrifying Argent Witches, a fan rewrite for the Lunars.