Legs are fantastic for healing when you're in Light Arts, arguably BiS, but they don't look as attractive if you find yourself having to shoot cures while in Dark Arts.
The other options I see for the slot are the following, offering different pros and cons compared to Academic+3
Vanya Slops
(-) -5 MND, no -Enmity, no base Cpot (but you can probably cap it regardless), -4 Skill
(+) ConserveMP+6, don't have to rely on Light Arts, cheap/free, can use on multiple jobs
Kaykaus Slops +1
(-) ~20mils more than Academic+3, -4% base Cpot, -24 HSkill
(+) +3 MND (or same -enmity), CpotII (set bonus), FC+7%, don't have to rely on Light Arts, can use on multiple jobs.
There are also 2 options that Oraen didn't suggest to you
1)
Head => Sublimation is arguably inferior if you have access to Refresh3 (very cool if you like Subli though), but this piece still offers a pretty huge amount of Magic Accuracy, especially if you can use the set bonus. Think it's BiS in that regard, for now at least?
2)
Feet => These feet might look like they're nothing special but they're quite unique as in their casting bonus goes beyond the 80% FC cap. They might allow you to perform one more spell during Magic Burst, especially handy if you're doing the SC yourself and then want to multiMB on those SCs.