Sure, but as you said, there's the latency in changing presets, plus it makes organization a lot easier (at least for the way I do things). Let's say I have preset 25-1 as my rhythm, 25-2 my lead, and 25-3 my trippy ambient chorus part. I always need to remember to keep them "together" and now I have 3 separate presets to level match. That will work fine if you don't use a lot of presets / only have one tone you use for everything, and may be perfect for you. But for me it's easier to have all of those in one preset.
My general setup is more along the lines of: a couple of clean presets, a couple of lo-mid gain presets, a couple of mid-high gain presets, with the "standard" fx in most of them (i.e. phaser, wah, drives, chorus, delay, reverb). And then if I have any song-specific presets I'll create as needed. And most of that will fit into one bank of 8 presets. For one of my bands I really only need two or three because we play funky jams; my other band is more of a standard rock cover band so I'll have more song-specific presets for that one. I keep the presets for the two bands in separate banks so I can tweak for the levels and mix of each band - otherwise I'd be tweaking back and forth way too much.
Hope that helps, and really, the best advice is: do what works for you. As you get used to the AX8 you'll find out what's the best for your workflow... there's no one 'right' way.