We've had our A5L since 2019. My previous tub was a 2000's era Hotspring Jetsetter, which I had bought used from a family member and refurbished. We wet tested the Bullfrog tub at a local dealer, actually a larger version than what we ended up with. The jetpacks are a great idea and you can easily swap them around to suit your fancy. Once a week I top up the tub, run my weekly tests, and wipe down the water line with a microfiber cloth, including behind the jetpacks. The design does allow some water to circulate behind them, so it's not stagnate at least.
My view on seating and loungers... our bodies are pretty much neutral buoyancy in water. Whether you're sitting on a simple bench in a traditional wood staved hot tub or a reclined massaging lounger seat almost doesn't matter all that much. In all the tubs I've been in, what I do notice is how well lined up the jets are to my body, and is there something comfy to rest my head on and gaze up at the stars. That is definitely the goal.That said, the lounger is my favorite spot in the tub.
In our A5L, the lounger does double-duty as a cool down seat. Sit with your back to the filters (there's a pillow there, too), and you're in a very shallow seat that is great to get your upper body out of the water and cool down a bit. I'm 5'10" find even the relatively shallow A5L adequate. Each seat in the tub is at a different height, so you just move around to what you like.I am just worried at 5'2'' that I won't be able to anchor my feet in the long and my head will end up underwater, or I just float on up. I really love the idea of a lounger and want it to work.