Thank you for the suggestions.
Tedclev: As you recommended, I switched the grain bill to 15% Munich, 7% Vienna, 3% Aromatic.
OClairBrew: I'm slapping my forehead for not thinking of using Cali yeast. Unfortunately, it's too close to brew day to begin a Cali starter, and the German Ale starter is already underway. If my first oktoberfake is well received, I'll brew another with Wyeast's 2112 (LHBS stocks mostly wyeast, not so much white labs).
BrewerBear: Good luck. Lots of 6-row in the linked recipe. I have read that a 90 minute boil is not enough to eliminate DMS risks in an ale with more that 25% 6-row (I worry I'm pushing it by using 30% 6-row in my own recipe). Also, plenty of hops in there, which I'm speculating may require some aging time (the recipe already includes 4 months of secondary).