May I defend EdiBot on two points.
First, she is best with a shotgun with range. The reegar forces her too much into CQC. Claymore is good, yes, but IMHO the Crusader/HVB/piercing with Geth Scanner can't be beat. That gun will double hit bosses, gives four quick shots (when fixed), shoots through cover without loss of damage, and gives Edi full damage at all ranges, so she can stay out of danger.
Second, again IMO, Repair Matrix has negative utility. Employ it too soon, and it expires worthless; try to employ it a millisecond too late, and it won't deploy and down you go. Concentrating on exactly the right moment to deploy RM is a distraction that can get you killed. Plus, it makes Edi a grenade hog competing with teammates who can actually kill things with grenades. I spec out of RM, and play her with the normal caution to stay alive, and that works best. At least for me.