Guild Wars 1 had completely different skills for pve and pvp, not just a "-xx% damage in pvp" bandaid. But then again, pvp was a separate activity and, even when mixed with pve elements, you'd still only be able to use the pvp variant of the skills.

BDO is a different monstruosity though. FG doesn't work when PA doesn't want it work, same goes for SA (just take the seasonal Kavali boss for example). The only way to mitigate CCs is the iframe in those circumstances and, unless we're talking 1h long iframe (like some classes have), even that is rather rng.

Overall, I don't think that the complete removal of SA is a good choice. For neither, pvp nor pve, regardless of the class. It's true though, that PA either doesn't want to or doesn't have the time to (inbetween designing mostly bad outfits that have mostly bad animation and clip horribly) properly test and balance the classes' protections and cc capabilities. Which leads people like Potato to resort to desperate suggestions, along the line of "Honey, the kid got dirty. What do we do? Bathe it or make a new one?"

Still, I don't think it is a good idea to introduce so many differences in skills behaviors between pve and pvp.

Tweaking damages, OK. But tweaking defences and CCs does not seem to be desirable to me.

Back on topic, removing SA alone will only benefit classes with large AOE or range. It won't balance anything if it does not come with other changes. 

or iframe classes ;)

Terrible idea, which won't "balance" absolutely anything. On the contrary. It will make the gameplay even worse than it is now.

Some people never learn from the past...

what needs to be gone is class modifiers and ranger awak need nerf. She has 0 gaps, iframe grab, insane damage, range CC & dmg, very good mobility. If she didn't had range CCs & Range dmg i would be fine but that's not the case.

What about classes without s-block? You think that it's available for everyone? Remove SA and left them without protection in PvP and PvE at same time. SA can't protect you against grapple so maybe delete grapples from game? Tons of people begin duel from: dash - dash - grapple. One class is faster with that second is slower, but when they grab and do good combo then enemy is dead in 85% situations. You wrote about resists and cc limit. Resists are capped in pvp and you can reduce it in your own stats. Second thing doesn't work properly for some classes.

they need to reduce or remove SA, SA should never last longer than 15 sec and longer CD on recast on any class, a class with more than 2 SA skills is garbbage, no class should ever have protection 24/7 and no cc skill should ever have SA on them, this game has turned into a SA stun lock joke, the problem is all these new classes arent good without them cause thats what PA had in mind at the start when making them, i think SA in any game is cheap, no game should ever have SA, SA should of never of been a thing to begin with, it was only made cause some some people have bad reaction time or dont think before they attack so they so they cry about it and poof SA is born, change all SA to FG and be done with it, if someone gets hit from behind with a CC uh ya that person should get cc for not watching their own back, not turn around and nuke the person that got behind them that shouldnt happen unless there is a gear gap, the game isnt fun when you have to play the SA timer game thats not skill but if they are going to keeping SA then ever class should have a grab to weave out this trash SA system, but people cry when you grab them out of their SA and then call players trash for using a grabs to break the SA so what did they do they added longer cooldown time to grabs which is BS if grab is the only way to fight SA why would they extend the cooldown on grabs but most classes have 4 or 5 SA skills and one SA skill's SA last longer than the grab CD thats cause all these people cried when they got grabbed out of it but thats the point of grabs is to kill SA skills, just like this 10% life DR buff in RBF is BS just so lower geared people cant ever beat a higher geared person, in the past few years this game has gone down hill thats why new players leave the game so quick, not only is this game a life drain its way to hard to get your gear up without playing 24/7 so casual players quit and i dont blame them why would i spend all my free time grinding just to blow stuff up and make no gains, i been playing this game since launch but cause i work 9 to 5 job i cant ever take part in any of the good end game pvp when i cant get a single gain, when the game launched the pvp was amazing but now its broken just so the last few classes they released can be worth anything and now those are the classes everyone plays just cause of the SA.