Halloween Beer you say?
I have no idea how this will turn out but its what I am planning to brew in a week or two for myself and a few friends (mostly hopheads).
Belgian Tripel base, hopped like an IPA, and beet juice added along with dryhopping.
Rough recipe outline is something like this:
12 lbs pilsner malt
2 lbs torrified wheat (makes me think of "terrified" wheat)
1 lb of flaked oats, debating on toasting them first
1 lb sucrose to help dry it out a little
1/2 lb Crystal 80 for color
1/4 lb of Roasted Barley for color
1 oz Chinook at 75 min
1 oz Columbus at 5 min
2 oz Galena at 5 min
Dry hop with 1 oz of columbus and beet juice.
Pitch WYeast Belgian Abbey II, let fermentation rise to ~75F
I have heard that beets can add a distinct vegetal flavor that I am trying to avoid by adding it after the boil (maybe extract color with some cheapo vodka and add that for sanitation purposes).
Either way, if you want to make an "interesting" beer, you are going to want to do something beyond a simple Amber Ale or basic Hefe.
If you are scared of adding hops, maybe something with chocolate or pumpkin pie spices? You did say you were making two kegs worth, perhaps make one accessible brew and one interesting one.