I think the Aquatica cabanas are an excellent value.
That said, at some times of the year they are better value than others, as their prices are season-dependent (meaning you'll pay more in July than you will in May or September). When is your visit planned for? We have paid as much as $89.99 and as little as $30 for a cabana rental.....the latter of which was an absolute steal.
The cabanas include 12 bottles of Dasani water, 8 rental towels, and a large locker (located right inside your cabana

). They are located in separate areas of the park that are staffed by Aquatica team members, and only those wearing cabana wristbands are admitted. Your cabana rental will also entitle you to 20% merchandise at the gift shop, as well as the photos taken by the park photographers. We were also given the opportunity to book a second rental within the following 7-day period at 50% off.
Personally, I would not pay extra for the pool view or premium cabanas. The "standard" model was perfect as it was (and the most cost effective), and were located in the exact same area as the more expensive cabana classes (ie, the "pool view" which bordered the wave pool). Loved that the sides tied shut and we could change inside (meaning we didn't need to use the change rooms) and enjoy an afternoon nap completely out of the sun. There is a ceiling fan in each cabana as well, which helps a ton on the hot and sticky days.
I post some pics for you, which might help

.