she had to die. there was no other ending.
sure, the DA will try to frame jax for it, but the body had been there for hours, the bullets won't match. He'll have a legal mess in episodes 1-2, but that mess with the new gang coming to stockton should be way more interesting.
finally, jax is single to bang whores and shoot it out on the streets of his own town, against Nero, who knows his ways inside and out. Should be a good season again, finally! Tara was dead weight, and once she decided to snitch, there was no coming back.