Reading Order

Witchblade to #109
First Born - First Look
Unholy Union #1
First Born - 01
Witchblade #111
First Born - 02
Witchblade #110 (this is about Magdalena's POV which is why reading 111 first is fine)
First Born - 03
Witchblade #112
First Born Aftermath

Broken Trinity and Pandora's Box are kind of w/e after that, but Pandora's Box comes after the original BT (only the parts of Broken Trinity that I could find are here)

Artifacts is being released right now with Pandora's Box (which is about to end) and will be 13 issues tying the entire universe together (just google names you don't know, like Tom Judge - he's from one of their other series I don't bother to read)

You'll know when to read Angelus since the Witchblade issues will mention it, after it starts it doesn't intersect with Witchblade directly

Tales of the Witchblade, Bearers of the Blade, Obakemmono and JLA (lol) are all just stories of the other people that have worn the Witchblade