Its the D20 and the FFG system I'm conducting this thought exercise with. As someone higher in the thread mentioned while higher level characters in the pen and paper systems can definitely mirror the MMO ACs, it takes work and experience to get there in most instances. The problem with bringing players from MMO to pen and paper is they expect their characters to be able to do all they can do early and just get better at it, while in the pen and paper your abilities can really shift and change as you go from level to level, multi-classing, or adding specializations(FFG)