Not all freehubs are alike so you basically have the classic Campa pawls and ratchet system, DT Swiss' is pretty unique, Mavic, Extralite use a synthetic material (Delrin, I think it is) close to or going partly into the hub's shell. No doubt there are other variations on the theme out there.
Bottomline is to first look at what the manufacturer recommends and try to understand why they do so. Then look at how you clean your bike and how that is affecting the lubrication of the freehub system.
Once you have a clear view on all of that you can fiddle around with various lubes, change your cleaning method etc.
I, for one, used to suffer from freehub bearings running out of lube because I cleaned the chain and cogs with an agressive degreaser and probably using too much of that good thing in the process.
The chain and cogs were squeaky clean and grease free but so was the freehub eventually..................
The problem went away once I started to use removable chainlinks and freehub bodies without greaseports....
IMHO, the wisest thing would be to design a freehub that would no longer require any lube at all. It's perfectly possible with DLC coatings anyhow and they'd take care of friction and sticky pawls in a single sweep. Heck, it would not even need any maintenance at all.
Short of DLC, I'd recommend Krytox (PFPE) oil or grease for both ceramic hybrid bearings and classic steel contacting surfaces as it bonds to these extremely well and does not get removed easily. Altough similar in formulation to PTFE (Teflon to you and me) it lowers fricrtion way beyond it and as said, it reduces friction in an almost permanent way.
It will even reduce friction on Campa's much touted CULT bearings which are quieted down by a parafin based oil. A neat solution but it's actually adding friction.....
Sorry, I'm ranting way beyond the attention span of most of you already.... Give it a try anyway and report back.