There are many different ways to pack a suit. A suiter on a roll aboard is not always that awesome (depending on what jacket size you are packing). I have a suiter on a 20" roll-aboard but a good portion of the time I use the "fold a suit" method (see the packing thread sticky).
Depending on how much travel will occur later you might want to think about a very large wheeled bag (sort of a hold everything bag, like a 24" roller bag).
If you are not going to need to wear the jacket etc. for a couple of days after you show up at the hotel, you can use the steam by shower or steam by blasting out steam from the iron trick.
Best of luck and congratulations.