Well, to put a different perspective in, I honestly care little to none about the aspects you listed: aesthetics, story. I skip almost every cut scene and quest dialogue and rarely more than glance at scenery.
For me it's about mechanics and challenge. Alex savage finally provided some challenge after a drought. Long time between Final Coil and Alex Savage with only things like Ravana EX and Alex Normal to hold the attention. Ravana EX was fun for a day or 2, farmed for another couple of days to get everyone in static a weapon, then mostly abandoned.
It could be improved though, without a doubt.
- A larger raid group would have been great, but pretty much given up on SE changing that (Alliances do NOT count and are crap so far).
- More variety in mechanics would be great. These are all small, locked arena fights. I can see why, but it could be better. Compare to coil t1 for example: all those hexagons at varying heights and position mattered. Or think of other games where bosses could be fought just about anywhere in open world. Picking your battlefield became a fun mechanic that way. Line of Sight, elevation, spacing, choke points, etc.
- Quantity. See above about the drought. Seems SE is in a pattern of 4-5 raid fights at a time with long periods with no challenging raid in between. That's really not enough to hold a raider's attention.
- Smoother progression of raid difficulty. My team has just beaten a2s and I was happy enough with a1s/a2s difficulty: it wasn't a pushover, nor impossible. Just starting on a3s, but considering that few have killed it, including none of the ~15 groups on our server who beat a2s before us, it's looking like a huge jump in difficulty. Smoothing out that curve would be good. Also no more stupidity like pre-nerf Twintania twisters please. (For those of you not around long enough to remember, in 2.0 the hardest raid boss had an essentially unbeatable mechanic. 1 group worldwide beat it after many weeks (months?) of trying and then SE nerfed it immediately after.) And a4s is beginning to sound like a repeat of that - not so much the 1 problem mechanic, but just sheer difficulty.
So a very different perspective. Interesting how SE tries to cater to both, and probably other, views as well.