5 frame neutral grab for Hayabusa and I believe his 6H+P is 7. It's not as easy to punish with the forward grab as in older games. I wouldn't worry too much about frame data yet, though. Things will likely change and I wouldn't be surprised if Hayabusa was sped up a bit in the grab department. You can't really play him like he played previously, so your worries are slightly justified there.
That being said, he plays a very good pressure game now, even better than before, and has (or at least had as of the most recent builds) a ton of guard breaks and fast strikes coupled with his awesome mixup potential. Ninpo is much faster, he can do a counter of sorts out of his ninpo now that puts you behind the opponent (though not with a ton of advantage, if any), and his grabs are as deadly as ever. That air grab is clutch for getting that extra push towards a wall or other danger zone.
I'll leave the Bayman questions to Doc or Rikuto. I haven't gotten to touch him. They didn't play Dimensions, though, so don't look for comparisons much. Rikuto has like a cumulative hour with the Dimensions Bayman lol.