I have, scattered throughout these posts, strongly implied the idea that you more or less kit-build your character. It started way back in the first post with the idea that for my 6e we'd use the 5e as the essential building block for all characters, and it got a bit further developed scattered around in various posts. In essence, your class gives you quite minimal class features, in 5e, but balances a bit what you can get access to, and your subclasses, how many HP and MP you get, but most importantly what class training you get access to. That class training, there need to be more options than you can actually ever take, lets you define your flavour. So lets say, for the sake of example, there are 5 picks available at every level, in every class (that seems like too many, but we're playing make believe here). You only get to take three of them... so you can opt for tank, more tank, yet more tank, or attack, attack, more attack or something in between and make your fighters...
This blog is written with the assumption that Wizards of the Coast lose their marbles and appoint me to be the lead designer for 6e D&D! It's not going to start as a serious play-test build, more outlining the ideas I'd like to see but if there is enough interest it might build up to more.