Honestly the easiest way to fix this to just make it so the a tanks attack power scales from vit. because as it stand right now 1000 STR = 1000 Attack power and since we have equal amounts of STR and VIT on our left side just make it so that 1000VIT = 1000 Attack power boom done now VIT acc's are awsome.

Then we tackle the problem of now we have a ton of useless STR on our gear. With this i suggest the replace it with parry. this way all tanks have a good amount of parry and all pieces will have crit, det, SS to deal with so an example piece would be this

57 VIT 57 Parry 37 Crit 15 Det

this would also solve the problem of tank BiS as we would not have all these useless pieces because now every piece has parry + the other 2 stats.