I urge you to try to ladder with just FO, and of course Blue Pots! Blue pots are for sure the solution to asura spamming without ygg berries! (if you're happy with a 20k asura).
Oh and as you stated, sinx's are able to put out huge amounts of damage in a matter of seconds, so the only way to prevent this is to put delays on yggs, the one thing that will save your life vs a sonic blow sinx~ ? :S
As Items/cards change, so does the way classes are played, the damage output of classes, the skills they use etc.., it's not just the players that change