I guess that there are two choices when packing up the boat- either undo the painfull gooseneck fitting, or unfeed the mainsheet and leave the boom up. Neither is particularly convenient.
We usually leave the boom up supported by the main halyard and held central by a bungee chord with plastic hooks. Everyone at our club thinks it looks like a sports boat and they've christened it the Ark Royal! The snatch blocks sound interesting but are they legal?
I always remove the boom when packing up the boat; that way I can leave the mainsail attached to it. I've resolved the gooseneck fiddling by replacing the split ring with an R-pin.
Note that I remove the mainsheet as well most of the time to protect it from UV and rain, unless I know I will be sailing the next day.
I now leave the boom on all the time. I have made a plywood 'H' shaped support that fits over the horse and supports the boom which is secured by an elastic that runs over the Boom and through the Horse to the rear D ring on the cover. The plywood has been varnished and is standing up to the weather really well.
Second innovation was to change the Goose Neck pin to a Drop Nose Pin (order by phone from Trident-UK.Com and delivered the next day approx 10 pounds.
The final gem is that we lost 2 ring pins?, the ones that hold the launching trolley onto the roadbase or front towing arm to the Launch Trolley; I discovered that these are available from any good agricultural shop (as in sells tractors etc) in bags of 5 for les than 1 in a chandlery.
If you want to cantact me I can send you a picture of our 'support' and explain how we put it together. d.stubbs1@ntlworld.com rgds,