I'm thinking of using the 4e DMG monster advancement formulas as quickplates for 3e monsters. I'm considering adapting the 4e templates as well. I like the idea of mechanically straight forward advancement and template application.
I like monster roles such as brutes and soldiers and artillery.
I like monsters having just a few themed powers
I think healing surges are ripe for stealing and applying to 3e.
I like passive perception checks.
I like the pathfinder/4e skill consolidation trend.
I like bloodied as a condition triggering effects.
I like the idea of first level characters having more hp as used in 4e/PF/BoXM.
I heard that charging does not need to be a straight line and just gives a +1 on attacks with no AC penalty. Sounds better.
I heard good things about the diagonals equal 1 move when used in play at the table.
For playstyle preferences I like encounter based powers more than daily powers.