> Your optimizations targets cases where a single key is used for a lot of data.

Yes... 200kb for each key is the price (max 10 times). Thats true. 
But it's not for nothing. It's, practical spoken, for ~1 second waiting or not while en/decrypting 1MB in internal mode.

> However uses where the key changes often for a limited encryption/decryption volume suffers from them.

Yes, that's true. It costs about 0.0005 sec. (or less) for each setKey(). So practically nothing.
But for that, it saves, for each object instance about 80kb (on my machine).

> Your inlining high optimization suffers from the same symptoms: it recompile the whole code up to eleven times.

Thats also true. But we get much more then we pay. 
_setupInlineCrypt() costs, on my machine, >= 0.001 sec. But that we get x times back.

So what is better? Pay >= 0.001 sec and get 20% gain back... or not pay 0.001 sec but also not get 20% gain?