Hmm, I just lost my post, so this one will be a little more brief and to the point (distant cheers of "yay!").
Honestly I'd much rather it was more like (for both sides)
Hard: 11-14
Moderate: 9-12
Easy: 7-10
That'd be pretty good as far as probabilities and such go for integrating with powers.
I think 10 for the easy defense is a little high. I am thinking of characters without any feats (Iron Will, Great Fortitude) to boost their defenses.
I like that idea, though we could quibble over exact numbers. To do that though, you'd have to drastically increase the damage being delivered.
Of course, exact numbers would have to be determined through discussion/analysis.
Also, whatever values are chosen, I would like a little leeway for "buffs" and "debuffs" to affect defenses.
In regards to damage, I can't really comment on that, as I am sorely lacking 4e experience. My primary focus is on balance, but I have read about how easy/grindy the higher levels seem, and I am all for making it a little more challenging for the players.
I was going to suggest that elites should hit players on a roll of 2 less than a standard monster, and solo 4 less. Meaning if a standard monster would have to hit the hard/medium/easy defense on a 14/10/6 (again, example values), an elite would have to roll 12/8/4 and a solo 10/6/2.
The reason for my suggestion was that I was under the assumption that elites and solo's had a higher to-hit than average monsters. I was surprised however, when I looked through the DMG's guidelines for turning monsters into elite and solo versions, and didn't find anything to that extend. A quick lookup of the 5 level 10 soldiers (2 elite, 3 standard) in MM revealed the same.
Perhaps they should have, perhaps not. However, I believe that discussion would be off-topic.