Re: Whats better..crecent moon, infinity or 6 socketed sword with 6x 5/5 lite facets?
I prefer Nova to CB, but that's just my personal preference. Neither one is significantly "better" than the other, they just require slightly different playstyles (Nova is "100% aggressive", while CB is "~75% aggressive").
In my opinion, you only really "need" either Griffon's or CM, but not necessarily both. Having both (on top of the Infinity-merc) will increase your damage quite a bit against monsters with broken immunities, but it'll actually decrease your damage against many other monsters that aren't normally lightning immune (that is, compared to having a few more +skills on an Orb instead of Cresent Moon - the orb will win sometimes).
As for that equipment, your resists & FHR would be somewhat low... you don't (entirely) need Griffon's if you equip the Infinity yourself (since you'll have decent -Enemy Lightning Resists from the Infinity itself)...
Personally, I'd settle for a orb+shield combo and stick the Infinity on a merc. It provides a lot more opportunity to make your sorc well-rounded.