billd91 has a very good point. AEDU would be a lot less 'in your face' if you could chop and change the powers you used from the ones you knew. Say at around 9th level, you've got 3 encounter powers available. Why not allow the use of the same one 3 times in an encounter? Why force the use of different tricks or expenditures of effort? There's no actual logic behind it.
Every argument (that I've seen) in favour of AEDU has a counter-argument.
Every piece of descriptive logic (that I've seen) to explain AEDU falls to pieces when examined properly.
I am a staunch supporter of all the exciting changes which the Fourth Edition brought to the table. However I do accept that there are problems such as what you describe.
My solution on the other hand is to push the system further. Think of a non-broken way to implement a greater choice of encounter powers.
The same goes for things like wish lists and treasure parcels: in the interests of roleplaying and cooperative storytelling, as well as fairness and fellow feeling, I have delineated an even more radical approach. [sblock]1. During the adventure, I roleplay the treasure. “You find a heap of gold coins and other valuable items in the orc chieftain’s chambers.” “You find many trophies, components, treasures and what look like magical items in the wizard’s library.” “You come across a well-stocked armoury.” The players can likewise roleplay what they found immediately: “We shove all the loot on a mule.” “Do I find a wand?” “Indeed you do: when you get out the dungeon, you can figure out what it is.”
2. Add up the total amount of treasure a party should get for a given level (add the gold piece value of the parcels together: there are tables on character optimization boards which give these numbers, but it is not hard to do). Divide this by the number of players: each player will have that abstract number measured in gold pieces, but the treasure can take whatever form they wish.
3. At the end of an adventure (not every session: that is too disruptive), the players can “find out” what they found in the adventure. That is, out of character the player chooses what his character found in the dungeon, limited by the gold-piece value of his portion. Players who cannot be bothered to choose can ask me for an item. I encourage the players to roleplay their discoveries and give colourful reasons for finding what they do.
4. This means that players are not limited to one item of a specific level. Under the official system two players cannot choose an item of the same level or get two low level items instead, et cetera. My system allows all the roleplaying during the adventure that people want, but very simple bookkeeping at the end of the day and absolutely no frustration. Indeed, I allow people to save up their treasure points for another level if they imagine some great magical treasure would suit their story better.[/sblock]
Likewise I love to overcome almost any onerous restriction with radical reflavouring (refluffing). Of course that sometimes requires an equally open-minded playing group. No Genasi in this world? My grandfather met the daughter of a mountain spirit: happens all the time in fairy tales.