Well, she certainly looks cool, but yeah, she's basically this trilogy's Boba Fett. Which is fine, I guess, Star Wars always has a character who is just there to sell action figures, and at least Phasma has a bit more character to her than Darth Maul did, and it's quite as over the top as General Grievous.
I'm sure she survived, in fact I doubt she had any trouble getting out of the trash compactor. For that matter, we don't actually see any of the main First Order characters killed, do we? Snoke orders Hux to rescue Kylo Ren, so if Ren is in the next one, Hux should also be there too, right? Might be interesting if they actually do hold on the same lead villains for the whole trilogy, which is something the other trilogies didn't really do. In the OT Vader is the only Imperial in all three, with the Emperor and Admiral Piett in two of the movies. Palpatine/Sidious is the only villain in all three prequels, unless you count the Trade Federation Viceroy, who is never really much of a threat. Count Dooku is in two movies, I suppose, though is role in ROTS is small and most of it was done by a stunt double anyway.