Frost mages needs to have you in a frost nova to shatter you, unless they specced into deep frost or whatever its called but im not aware that pvp mages do that. Aka you can counter alot of the damage with Hand of Freedom wich prevents ice lance from critting, well it used to be this way when i played my mage but its been a while. Paladin should use Hand of Sacrifice if they switch and back to hand of freedom on the next burst. The only way to prevent a counter spell is to bubble since you cant fake cast 5 counterspells without insane luck. Take a look on armoury and see if someone of them use pve gear and focus them if they do! Play agressive and dont try to wait them out since this will give them time to plan and less chance of doing mistakes, bring your totem farm with you when you move. Your paladin got aura mastery aswell wich makes you all immune to silence and counter spells for 10 seconds, a well timed divine sacrifice will help alot aswell. Its not a easy fight at all and your paladin have to use every tool he have to migate the damage, when they are out play defensive and heal ALOT, there is no way your paladin can heal this fight alone! Sounds easy on paper and tbh i have no idea if it would work.

4 destro locks? If hes multiboxing all spells will come instant and ususaly they start with immolate, save your grounding for the time he trows immolate, without immolate on the target you can compare it with a lava burst without flameshock. You can also save grounding totems untill after immolate so your paladin can dispell them wich is hard since there are 4! :P Tbh im clueless how to kill even one destro lock but we ususaly spam purge off his buffs if he gets blood lust to avoid that atleast then we try to drop a fear on him and a hex after that. Hopefully hes not UD but killing them with healers up is a lost cause.

Never faced theese FaK teams so i cant help you out there!