Draft Control
You have a good question and I don't have an answer, but, perhaps some other ideas can help.If your boat was used in charter the sails probably have a lot of use, and probably draft too. In this case control of the draft of the main and jib will help with upwind performance. Backstay adjuster: Increase the backstay tension on upwind legs to reduce headstay sag and reduce draft in the jib. Don't know if your boat has one but this would be a very cheap addition if a line control adjuster is used. Hydraulic adjusters cost a lot more.Main adjustments: The main should have a cunningham adjustment to tighten up on the luff and reduce draft on upwind legs. Also ensure the outhaul is tightened up too.Depending on the course an asymetrical spinaker could be an inexpensive addition. Prop: this is an expensive item for a boat like yours but the speed increase is generally worth the penalty in seconds per mile in the PHRF rating.The high-cut sails will cause only a small disadvantage, maybe just a few seconds per mile, so don't let this psyche you out. Put a lot of effort into tactics and having a good start as this is where you can keep from loosing those seconds.Another point, if the boat doesn't have an ablative paint, get the bottom scrubbed to reduce drag.Pre-race preparation is important, checking tides, wind currents, etc. Hopefully someone else might have some ideas. Good luck.