I had this idea lately...
Instead of having one content aviable for both 10 and 25 man, I'd like to have:
1) Some rads that are only 10 mans (like Karazan was), which serves to gear up new-raiders and also drop badges
2) Some raids that are only 25 mans, which are more oriented into story progression, and drops high tier-badges.
So people that are fresh 85, would start doing 5-Man Heroics, then move up to 10 mans and then move up to 25 mans. After this they can also move to 25 man heroics.
Also, there would be no 10 man heroics, because I think no one really do them... they just move up on 25 mans.
What do you think? Yes, it would be "harder" or "slower" to gear up alts or your character, but it would be more appropriate than jumping from 5 mans to ICC25. An intermediate passage would be 10 mans. Every new 25 man content when relased, also have its 10 man content related (ICC had 5 Mans, and 25 Mans, they could have added a 10Man related to the ICC story following my idea), so Blizzard can continue with their "progression" strategy (you jump directly to the new content):
At the moment its 5Man Heroics Drop Badges -> Get Tier -> 10Man Content of the same raid, 25 man content of the same raid.
I think it would be better and nicer if 5 Man Drop Low Badges/Epics -> 10 Man content of a raid -> Get High Badges/Low Version of Tier -> 25 Man raid High Lvl Epics/Tier.
It would require more work and effort from Blizzard, but I'm sure that if they drop those stupid 1 Man bosses raids/Archivon like style instances that are a real slap in the face to the WoW Community as they are really wasted piece of lore like Malygos or serve nothing but to easily gear up randooms and put some more effort in less but longer and better 25mans and also NEW 10 mans, I'd be happier.
What do you think?