I rolled destro a long time ago because I thought having a cast time for DoT was crap... and it is! So many classes have fear immune abilities its crazy! Y should a lock have a the same cast time for a DoT as a mage or shaman which does direct damage?
The fact of "no burst" is true, besides an instant SB every now and then...
You forgot to mention being silenced! Shadow is the only school and aff use, so if u can locked out of that school u can't use anything for 4-8 seconds!
Since they will never change this, my advice is to roll destro, burst is insane and 1v1 you will be able to hold ur own against ANY class... U mentioned rogues... just seduce them when u get CS, if they trinket seduce again, and now they don't have a trinket! Shadowfury, fear (will only be 2 sec but will give u more distance) then light them up!