E-85 is definitely addicting because of how much power our N54's/N55's make on it. My 335i is a completely different beast with E-85. I had my doubts about using E-85 as well but after I tried it I won't ever stop...
Get a JB4 and DCI then put about 5-7 gallons of E-85 then top off your tank with 91/93. I'd go with Map 2 but that's personal preference. I know you don't have downpipes but I used to run Map 2 all the time without DP's and my car ran strong. Go either with Map 1, 2, or 5. I'm honestly not a big fan of Map 5 tho compared to Map 2.
And FYI, your car might run a little sloppy at first but give it time to adjust. Maybe a few hours, maybe a few days.