I really like the following in both the Lutron IR and LutronRA 2 dimmers:

1. they both have a nice small remote that one can have in the bedrooms for a single light control
2. a favorite button to bring the lights to a predetermined level on the remote
3. a delayed off where the delay period is determined by how long the off button was pressed

I would like to know if all three are possible with a z-wave system. The smallest decent one I found is the Tricklestar 200ZW-US-W Z-Wave Remote Control:

www.amazon.com/Tricklestar-200ZW-US-W-Z-Wave-Remote-Control/dp/B002NHMYAM

It only has two buttons on the outside which per the description can do dim hi/lo and on/off. What about delayed off? Is it possible?

the delay is setup on the hardware (in your case zwave light switch) or software if you use software. even for the hardware though you have to program it to the level/delay you want and each manufacturer has their own process to do this.

Is on-the-fly delay time for off not possible with z-wave?