I have no clue how the creation kit works, never even looked at it (lol).  I had to search just to figure out how to see the health of opponent and only knew you could do that from a response to a question I asked a couple of weeks ago. 

Just retested and got the same figures.  For reference, my Fortify potion is 43% and in my active effects, both Rage and Fortify Marksman are showing up.

So Rage is affecting damage but the Fortify potion is not as I'm getting the same damage without the potion.

I am patched on PC if that makes a difference.

OK, I had a save from the Volkihar Castle.  Went back, took vampire lord, went back and recrafted my Fortify Marksman potions.  Here's my results from the same process but with Vampirism (in Orc form):

Dragon: 905.00Punch Only: 63.36 (almost double non-vampire)
Potion Only: 41.58 (which is almost identical to first test as non-vampire)
Berzerk Only: 83.16 (slightly higher than non-vampire)
Berzerk + Potion: 83.16 (slightly higher than non-vampire; however same damage as Bezerk only; seems to confirm the potion is not working at all.

Ah, that's the problem. The unofficial patches modify Fortify Marksman potions to only fortify Archery damage, rather than all physical damage as they do by default.

You can fix this yourself pretty easily -- unfortunately, this is about the only major exploit that doesn't already have a "revert unofficial patch fix" mod already on the Nexus. All you need to do is download and install TES5Edit, then run it and follow these instructions. If you have trouble, let me know. I'll see about giving it a try myself, and if I can get it done, I might just upload it to the Nexus.

Don't stress on it..I've already gone without it and posted the build a few days ago.  Still, it would be nice to have the option on a future build.  Thanks for chiming in.