We returned to Carnival after being away for about 10 years, and having cruised with them twice before.
Overall, our experience was mediocre.
We flew into George Bush International (Houston) and stayed at the La Quinta Inn east of the Airport. For the money, the La Quinta was nicely appointed and well maintained. GB Intl is located in a descent area of Houston. The shuttle to/from the cruise port (Galveston Limo) was a bit pricey ($95 round trip per person) compared to cruising out of Florida. You can fly into Hobby Airport, but the fares were higher, and the area of town isn't as nice. While in Houston, we checked out NASA space center (good pre-cruise activity). This required renting a car. Budget Rent-A-Car had descent rates, new-clean cars, and was easy to deal with.
Location was good, quick access to most frequently used areas of the ship. Love Balcony rooms. Room was on the smaller side, but was comfortable.