Derren said:While everyone is happy about spell less ranger, a other information from Mearls gets overlooked.
Fighters are expected to wear heavy armor.
Apart from the thematical restriction it also says a bit about how armor will be balanced in 4E (no more Dex - AC balance like in 3E).
Right, you could easily go armorless and ditch the full plate + heavy shield combo by having a dex of 30. The full plate + shield combo was affordable by 3rd level, by the way. I'm not sure what it takes to get a dex of 30. More than 3rd level though.
A high-level 3e fighter with dex 16, mithral full plate +2 and a heavy shield +2 has an AC of 27. To do this unarmored requires a dex of 44.
A lightly armored, shieldless fighter in a mithril breastplate +2 would need a dex of 30 to achieve AC 27. Well, he would need that if his max dex bonus wasn't +5, making a dex higher than 20 useless. He could of course get a shield, but that may not fit the theme you want.
At this point, I'm not sure what dex-AC balance you are referencing.