Just bothering to hit the head and use a proper PA rotation should bring any class past 1 mil at this point.
Jet Boots, Level 90, Jutus +35: Pretty much exactly 1 mill damage just doing perfect attacks on the head. Sounds about right.
Strangely enough, Photon Arts by themselves don't seem to increase that number by any noteworthy amount (In fact, Strike Gust seems downright detrimental if it weren't for the Shifta effect). The big gains I get are from setting element, shifta and remembering to rapid boost (and then two additional big chunks using alliance and drink boost). That pushes it past 2 mill.
Finding that out felt a bit meh, I had expected more from attacks that cost me a limited resource. But I've been a lot less PP starved since.