Thanks for the advice, both - appreciate it! The Duty Support idea was sound advice and have given that a try - I guess the test will be whether or not I can remember what I've seen with a team of players!
And yeah, getting caught off-guard has been a big problem - although a bigger problem seems to be that when I move to avoid AOE attacks I consistently get hit by them anyway despite the fact that, on my screen at least, I was outside the AOE - so I'm wondering if there is some form of lag issue at my end to be honest.