I usually follow the same routine - cards first, then LoTW. My reasoning for that is: The LoTW Q's are guaranteed, the paper ones are not. If you submitt the 55 LoTW Q's first and the checker has an issue with one of the 45 cards, you'll come up short.
Don is correct. Submit your LoTW-only application this weekend, then once you have that squared away, assemble your physical cards for field checking at Dayton. I would suggest using the online DXCC system rather than the older traditional paper application. The real benefit to this as far as Hamvention is concerned is you pay ahead of time, online so it eliminates that aspect of getting an application field checked.
Who knows, I may even be the one checking your cards next weekend! I don't know my schedule yet for volunteering at the booth, but it will probably be sometime on Saturday. On behalf of all my fellow card checkers, though, I would ask a small favour--with the cards in the proper order, please put the labels facing up. With a huge bundle of applications to process up there that cuts down the processing time for the next guy