OP, good summation and good ideas. Sounds like they were trying some new ideas with the Essentials characters if you ask me. There seems to be a consolidation of powers consensus, I hope there is also a consolidation of magic item consensus. There are so many magic items out there now it is as boggling as powers. Although if they streamline powers then they would probably also get some streamlining of magic items as a trickle down effect.
Also, I hope whatever new power structure they use in 5e you don't "forget" lower level powers as you level. That has always been difficult aspect of 4e for me to get over. Makes no sense whatsoever, I don't care what long winded stream of rationalization gets used to justify it.
I'd like to see a complete overhaul of magic items. I thought they were on the right track with the common/uncommon/rare/artifact differentiation, but they didn't go far enough. What I'd like to see are more "pseudo-artifact" magic items--which would be rares--the type of items that PCs really look forward to finding and that are game changers. Commons would be stuff like potions and other expendables, while uncommons would be your garden variety enhancements of what a character can already do.
But the key point: bring the magic back to magic items, and less dependency on underwhelming daily powers.
As for powers, I'd like to see more of a mechanism for powers to improve by level. So, for instance, an at-will power wouldn't remain static but add, say, 1 HP of damage every two levels.
Secondly, I'd like to see powers creep a bit closer to simulationism. I think the aw/e/d/u approach was a nice try but doesn't really work out all that well or, at the least, is awkward and sort of a patch for what I think D&D should have done, and seems to have been avoiding every since its inception: move towards a power point/mana/fatigue system. I'd like to see WotC take something similar to Ars Magica or Talislanta and adapt to D&D.
In a more "realistic" approach, you would never forget powers. You would both be better at them but also know newer, better powers. It has always bothered me that the only difference between a 1st level Wizard and a 20th level wizard casting magic missile is the INT modifier; at the least it should include the half level bonus, and maybe quite a bit more.