I have no actual sources or data to agree or disprove the Spell speed issue, so I'll just let that case rest for now.
That aside, I find it interesting how you assume you'll have 100% fey glow up based on the stat weights (actual values drop slightly, but that's not the point here)
I just played around with Ariyala a bit, you piqued my interest about the whole i90 accessories having more weight. I ended up creating two builds: One with i90 accessories (2 accuracy melded, 3 "damage" melded) and the default i110 set. While aiming not to overcap accuracy too much.
This resulted in the follow stats increases for each build:
i90 accessory build (4 accuracy over cap)
+163 crit (34,07)
+209 Spell speed (56,43)
+109 determination (26,81)
+278 intelligence (278)
Combined value is 395,31
i110 build (3 accuracy over cap)
+168 crit (35,112)
+178 spell speed (48,06)
+42 determination (10,33)
+303 intelligence (303)
Combined value is 396,50
Conclusion: After spending millions and millions of gil or hours and hours of spiritbinding, you're at -1,19 value compared to the full i110 build. I'm still not convinced.
ps: Interesting how we ended up from the food conversation to the i90 accessories (not that I'm complaining, gives me something to do)