The Intelliframe is the best frame for a Mag, but the DYE frame also works well except it doesn't come complete like the Intelliframe.
The Intelliframe is not an electronic trigger frame, but can be wired to run your hopper or warp feed.
I have no experience with the warp feed so I can't answer this question.
The Mags in general are probly the most simple gun to maintain! You want to clean the breech and bolt and oil the gun after each use, but don't split the valve halves unless you need to repalce the reg seat or unless you have a new one to install when you do take it apart!
Forgrips are a matter of personal taste, I like the way a 15* verical asa with a gas thru-grip feels the best. The 15* kick puts your wrist in a more natural position then if it were straight down. Expansion chambers make a nice forgrip due to their size, even when running HPA.
I hope this information is of some help to you.
AND ON THE 8TH DAY GOD CREATED THE AUTOMAG!!