You should consider speccing into Light or Cold, since they both have nice defensive passives, and Cold also has Ice Elementals which give a defense and 15% DR aura. You'll probably need to re-summon them frequently, but it's better than dying.
Fire set is kinda meh, honestly. I'd recommend swapping out for some RW's, Crafts, or even some TU's can be nice. Just check around for stuff with fire spell, +skills, and fire pierce if you want to stick with that element. Can't think of the name, but TU Jared Stone is a nice starter and allows a shield for more defense and stats too. Definitely try to get some reanimates. I orbed 10% Skeleton Reanimates on three pieces of my gear for my bowzon and the screen floods with reanimates. Helps a lot with incoming arrows, but still sometimes an arrowside sneaks through, so just be quick with dodging and you'll be fine.
For now, I'd actually just recommend grabbing the TA charm and then proceeding to try to pick up some more charms. I'm not sure you're quite ready to begin heavy farming for gear in TA yet. I'd also add Destruction Nihlathak runs into each of your games since it's guaranteed 2 sigs per run and a unique with chance of being SU.