I don't care if it's Phoenix Saga or no Phoenix Saga, Angel or no Angel...they need to bring that cast back by any means necessary. Singer leaving sucks ass, but they could certainly do worse with the replacement. Xavier being played by someone else besides Stewart after the first two films...ugh.
And please let this be the last one. If they keep doing them, one is going to suck eventually.
The "Previously on Heroes" voice over specifically referred to him as "evil". Could be misdirection, I'm not sure. I think we have three forces at work: -The Heroes -The Evil Menace, led by Claire's dad.