Personally, I am a fan as well as some friends that play on eGO HC server. We love the "Ground and Pound" aspect of HC server. Although there are vehicles it doesn't impact the "skill level" I feel is tested in a mostly infantry HC server. If jets and choppers were added I would be in the chopper ALL DAY farming kills. When I want roll over people I just hop on a normal FLY maps server.
Adding Karkand map out of B2K x-pac would be cool, but as far as vanilla maps go I wouldn't recommend it. Just think, Operation Metro HC 64 players? I threw up in my mouth as to how LITTLE skill is required to sit on a AMMO pack and chuck grenades or shoot RPGs down stairs and hallways.
No disrespect to you Dib, but I really hope that doesn't happen to the Aftermath server.