If you're thinking of a hybrid, I would try out a lower tension on the poly. If you're going a whole stringbed on poly, good luck to your arm. Either way, I find that keeping the tension on the poly about two pounds below the mid-point is a good place to start. Since you're looking for a crisp feel, you could try at the mid-point or one or two pounds above mid-point before you decide if you want to move up or down. I think what I'm getting at is don't start too high!
Of course, there's no rule that says you have to go low with poly, but this is just personal experience using Luxilon for the past six months.
Lastly, poly "going dead" means the strings don't feel crisp, they stop shifting back to their original position, and you find your arm tiring out from having to put more effort into every shot. You'll notice when poly goes dead because your arm will start to go dead as well. Essentially, the string stops helping your shots and does nothing for you, so you're forcing every shot with your own arm strength.
I hope this helps! Again, I've only been using poly for about six months and I'm sure there are people on these forums who have been using poly forever.
