With the scav lock-on mechanic, if you stay hidden from their line of sight for 2 or more minutes they lose interest in you, helps when you're pinched by sniper scav etc.
Also worth noting you only get the free healing from therapist every raid until you pass level 5(think its level 5) after that she charges you based on missing health and injuries (fractures etc). Its much more cost effective to use your own healing tools (specially grizzlies) to heal the wounds and on top of it you get a bit of player exp for healing out of raid (use to be Vitality skill too but that's just bugged now)
Oh one more addition possibly, when you get damaged guns in raid where the traders wont take them you can right click -> disassemble and sell every weapon part to mechanic/skier/jaeger (mechanic most weapon parts, jaeger for knives/silencers/sniper items, skier for the rest) and the damaged barrel to fence. Nets more cash than just selling it as one damaged weapon to fence.