Continuation bet something like $60-$70 on the flop. That will make 3 betting and getting it in on the flop much more standard and much less about how often villain shoves "deep stacked".

With the straddle, you're effectively playing 110bb effective, really a bit shorter if you consider the effect of adding another blind. With those stacks and with the read that he's flatting wide enough to have K8o type hands, this board texture, and your continuation betting frequency and general weak tight play, 3 betting and getting it in sounds great after continuation betting a larger size.

Just because your continuation bets have been called the past few times (what like 10 times? Variance on that sample is not significant), is not enough of a reason to quit continuation betting air. In fact, it makes you MUCH easier to play against and sets you up to have awkward decisions in spots like this one. Instead of thinking AA IS THE NUTS WEEEEEE, now you're thinking something like "oh he thinks I'm weak tight, so my flop 3 bet gets too much respect, so I can't get value". That's why you should be continuation betting still. The implications of the continuation bet go very far beyond that first flop bet.