Attack Crit Cap

I've wondered if there is Crit or Attack Cap that when you have more it's only visual like you have 2000 but its not making any difference ? sorry for bad english

 

No, but crit strike is subject to what is called a softcap, depicted reasonably accurately on this paint diagram:

The more you get, the less benefits you receive from it. I dont know if Strike Resistance is still a thing, but players generally agreed that 700 to 800 Crit Strike (post-mitigation) is about as much as you need. You will need to have appropriate stat value to make up for whatever Strike Resistance your average opponent will have. Note that Crit Strike doesn't gradually decline in efficiency, but rather at certain thresholds.

 

Strike resist is still a thing and people have about 650-700 of it without scrolls/agility ms. 1400-1500 crit is enough.
10/10 paint diagram

 

Can you tell me which other stats are usefull for assassin because i have 1.8k crit already ?

 

too much crit...1500 for sin is already enough then u neeed 5.5k accu and 2200 mag accu...depends always on ur gear...those are BL Stats, anyway if you dont have archdaeva set u can put x2 crit/mag accu and then attack/mag accu x5