As a long time landyachter (full size) and short term radio version one, I have read this topic with interest. A few things have jumped out and I feel the need to comment, you are welcome to shoot me down if you wish (or should I put whisk given the spatula ?)
Vang/kicking strap are not used on landyachts as if you sail them as you should, fully sheeted in all the time, they have no function. You will learn to tack downwind using apparent wind rather than true for speed around the course. You very barely ease the sheet except for bearing away then pull back in as the speed rises.
It was in the 80s that gooseneck or whatever you wish to call it was largely discarded on the full size yachts which did not use a wing mast. Reasons as above, as the boom became a simple function of keeping tack and clew apart and a place to attach the mainsheet.
The Batt (or is it Bat, ) was designed for HK by a well renowned Land Sailor in the US and uses some of the thinking he has gained over the years, as well as using KISS for commercial reasons.
When you set it up, make sure that the mainsheet can be pulled in hard at full extent of the lever. Then it will be enough slack at the other end of the range. Much of what you may have learned as a water sailor is irrelevant, even if you sail very fast boats. As a full size "wet" sailor, all I had learned with fast yachts like Tornado, International Canoe, 12 and 18 foot skiffs had to be unlearned when I took to wheels. The same applies for the RC ones, Marbleheads, 1 metres and multihulls are irrelevant to the RC landyachts.
Thanks for allowing my ravings.