Well we do use the same gear... and I'm wondering how I'll play it too.

I dont' think I can cover both SMN and BLM needs at the same time, but Summoner is definitely my main.

Summoner and Black Mage share the same gear and all my Materia is based on Summoner choices not BLM.

I went with mostly Crit (which we share a desire for as SMN and BLM)... but... because the Summoner has Ruin 3 and it costs about 1000 MP to use it outside of Dreadwyrm. As a SMN you stack Piety because the damage Ruin 3 does is so good that you WANT to use it outside Dreadwyrm and your DPS numbers will definitely show it.

So I packed a lot of Piety Materia on as well... so as to where most SMNs will have 9000 MP I've actually got a full 10,000 MP which is another full Ruin 3 over and above any other Summoner, and I never run out of MP to cast Ruin 3 with. (Come close in the Lava Scorp fight though in Sohm Al Expert).

My Crit is at 1050, but Spell speed is only 677 unless I swap for the Shire Hat, which drops my Crit to about 990 and raises Spell Speed to 720.

I am thinking this gear will probably be ok for BLM too, as it will probably affect the number of Fire IVs in the Enochian Fire Cycle.