It's not unplayable at all. It can be frustrating but you're not at a COMPLETE disadvantage without those guns and perks. It is disappointing that being said.
It really, really isn't that bad.
Blink/shotgun is rough, sure, but the people that are actually good with it aren't nearly as common. People still run in straight lines for you with it
The Thorn is outright demonic, but you just have to remember you're dealing with one and play a bit safer than usual.