Yes, yes
Hanked-on sails make for a smoother laminar flow across the sail which would make the headsail draw better,but you would be swapping a roller-furled 150 jenny for a set of hanked-on sails. Mainsail battens will improve the shape of the main in most if not all wind conditions. An 18 yr. old mainsail may look good, but that doesn't mean that it isn't stressed or stretched. What do your telltales tell you when you adjust the sail? An adjustable backstay would help with the shape of the headsail in any event. You can sail a bit faster with the mods you ask about, and I guess that is what racing is about, but you will lose the convenience of roller furling if you choose to hank the sails on. If you hadn't thought about it, it would possibly mean additional crew. It's harder to single-hand (actually, dangerous)to go forward to make sail changes while underway. Im probably preaching to the choir here, but as with everything else in life compromise means giving up something to get something else. Upgrading the main may be a good idea whether you cruise or race. Just how bad do you want to go faster?That's my take on it. Tom Ehmke