Personally, it seems like Rangers are going to be largely redundant with Rogues. I suspect Favored Enemy will be gone, because the designers have talked about how they didn't like the way it meant that the DM, not the player, chose when the power was active. After that, it's just a matter of ditching the lame spell progression (hey, that's what Druid Training will be for, right?) and there's nothing but nature-themed fluff keeping you from being 'lightly armored skill-using bow striker' vs 'lightly-armored skill using stabby striker'. Sounds to me like that could be handled with power choices. Not that I am optimistic about this happening.
No Attacks of Opportunity for attacking an armed opponent while you are unarmed. There's ALREADY a penalty for fighting unarmed. It's called 'your opponent is armed, and you aren't!'
In fact, I would love to see Attacks of Opportunity reduced to almost nothing. Or even nothing as the default, with only 'sticky' characters being able to pull them off. There's ALREADY a penalty for drinking a potion while standing in front of an ogre. It's called, 'you're standing in front of an ogre, and you wasted your turn drinking a potion!' Unfortunately, it sounds like the current plan is to keep them largely the same, and then add bonuses to AoO for Fighter types - so much for those 'mobile combats' they keep hyping up!
Potions. I really want to see some kind of horribly non-simulative rules which limit the number of potions you can drink per encounter, or per day. Maybe it's like the magic rings, where you can only wear one on each hand - drink too many magic potions, and the magic fields start to interfere with each other, or the alchemical components combine in unhealthy ways, or something. Potions would be much easier to balance by cost if you could just assume that players have access to no more than X number of potions.
No Attacks of Opportunity for attacking an armed opponent while you are unarmed. There's ALREADY a penalty for fighting unarmed. It's called 'your opponent is armed, and you aren't!'

Potions. I really want to see some kind of horribly non-simulative rules which limit the number of potions you can drink per encounter, or per day. Maybe it's like the magic rings, where you can only wear one on each hand - drink too many magic potions, and the magic fields start to interfere with each other, or the alchemical components combine in unhealthy ways, or something. Potions would be much easier to balance by cost if you could just assume that players have access to no more than X number of potions.