Can't provide any first hand info on the masthead vs. fractional rig, but I think the deep keel points to weather quite well based on what I have read and limited experience with other boats. Having said that, outside of a few small boat, day charters, I have almost nothing to compare the Cal to hands on. My recollection of the day charter boats is that they were all slugs compared to my Cal.
On the lake I sail, the only other boats to play/race against are Oday 25, Oday 302 and recently added Catalina 250....but I have yet to see the sails on the Cat. Other than many hours on my Cal, most of my experience is on much bigger charter boats....difficult to draw any comparisons. I would comment that with the original genoa on the furler (fractional), my Cal has significant weather helm anywhere over 8 knots. (I am working on tuning to help that...just purchased a Loos gauge) Although my sails are obviously aged, they were well taken care of, possibly lightly used, and do not show excessive wear. I reef the genny in around 12-14. I have a swirly and gusty place to sail, so that plays a part in the reefing decision....I think if I were in consistent 14 knots, I might feel OK with the full sail...I think heel would be uncomfortable and compromise speed over 15.
I think I am faster to wind than the Oday 302, but he usually out runs me. He lives on his boat part time, so he has a lot of weight in there. I've circled back to make sure there was nothing wrong with the Oday 25 when we raced.
The traveler will barely center the boom. Not that I know a lot about racing, but I suspect you will want to modify that system if you want optimal performance from the rest of the boat. As you say, previous post address some ideas for that mod. I'm not giving up the cockpit space to expand my traveler, but I am looking into getting rid of the stop pins and putting something on there that could actually be used effectively while sailing. I'm on a narrow lake, so I tack a lot. Right now I pretty much leave the traveler centered (compromise), which does not center the boom. I do have the Garhauer rigid boom vang, which is a great mod.
I'm starting my racing career this spring. I'll be crewing on a Thistle and a Highlander, so that experience will likely give me more insight on how my Cal handles.
Sure wish we were all on the same water....just a dream...