Often pitchers will be a tick slower starting than in the BP too.
My thoughts on Hall:
His FB is pretty hittable. Not much swing and miss in it. As noted... a bit slower than expected. Hopefully, that picks up a bit more.
Struggled early with breaking ball control early, but 2nd time through he seemed to calm and got a lot of bad contact and swing and miss.
He pitched around a lot of foot traffic, so good resilience.
He did well in the debut but didn't look overly special either. Hopefully it has to do with nerves more than anything and he show more in coming games.