It is possible to set your expectations too high and set yourself up to disappointment. You have cruised before so you know that the cabins aren't "spacious" but extremely functional.
Go with the expectation of having fun and roll with any small problems. If any bigger issues happen then deal with them right away, before they become big problems that will leave you with bad memories.
I know a couple, who used to post here, who booked their first cruise on Celebrity Cruises, in an outside cabin. They were upgraded to a suite and it was a wonderful cruise. They booked their second cruise, in an outside cabin, and did not receive an upgrade. No daily canapes, butler service, special cocktail party or dinner with the Captain. They hated it and, as far as I know, haven't cruised again.
That is an example of setting your expectations too high.
Go: Enjoy and have a wonderful cruise.