Vicatman,
Well, it sounds like you like the boat you have. I don't know where your I-17 driver would rate. So, I can't really judge from that.
Anyway, all opinions aside, you will probably really enjoy the spinnaker. Most of the I17R guys that I race with are using a spinlock block for the spinnaker halyard and rachamatic blocks(4) for the spinnaker sheet. We also bungee the spinnaker sheet and halyard separately to the rear beam to restore some type of order to the boat. Many of us have also installed a cam cleat to the aft of the daggerboard well to lock-in the spin sheet say on a distance race or if we want to trap out and control with traveller only.
Just my 2 cents worth on the spinnaker set-up. I gotta at least talk sailing since the next race is until April 3-4.
Tom