I don't think surplus makes any sense at all. If I want to play a whole bunch on one class, then why do I have to hit a ridiculous artificial cap? I also don't buy the argument that it helps casual players, or the idea that punishing hard-core players is anywhere near a reasonable solution.
If it were me, I would remove surplus and guardians favor. If I spend more time leveling, then I should progress faster than someone who doesn't. That's just how the genre works and should work, in my opinion. I think every casual player in every MMORPG ever created understands and accepts that they will simply progress slower if they play less. I guess I just don't understand the logic behind changing that idea, especially by punishing hard core players.
On one final point, I can hit fatigue on my CON and THM in about 2 days each (a couple levequests, and a few behests gets you there pretty darn fast...). I don't have the stats, gear, or desire to play a DoW, DoH, or DoL. The system pretty actively prevents players like me from having fun by making good progress everyday on what we want to do. All so some other theoretical player can try and keep up? =/