Don't take me wrong.
I'm using !J from my own choice, found it the perfect way to achieve goals I was given. What I mean about articles and blog/article overrides is that, I need to push my own plugins to add special fields that are an easy to be modified by clients. K2/Cobalt/Seblod/etc are ccks which needs weeks to learn from its technical area because they want give you too much flexibility, I simply see a way to make articles more flexi, even by an internal mechanism for that. So what I really see is a way to add fields and then go through it by own alsternative layouts, no matter you override menu item nor general layout. I find myself quiet often in need to make my own menu link overrides because of weird needs, on the opposite I like to keep things simple. The next thing which is missing hard is current inheritance level which gives you one global scheme, but on the menu level it will give you headache. I know k2 is great for that, but I'm not talking about my own super-easy extensions that I prepare for short/local community. nor third party things
I am super aware of that this is a totally insane thing to make all devs happy, but I simply see a potential in that little, underestimated article system which follows me since J 2.5. Finally, the point is to give a way to make own layout/override which uses internal field system and then, give the developer a loose from making plugins. That's my point, I would really choose that way in areas of product pages etc instead of using super extensions that give too much overload (or my own ones).
At the end, I don't put any critics in that area though blog/category layouts need some love. If I were more into core then I would try hitting the community long time ago.
More over, you want to reduce core size which I really appreciate, but I'm wondering why you put FOF from akeeba which gives devs more overhead:) Just an example.