I have a new mainsail being built. There are endless versions on the web so I'm applying a few on my CAD program to get a feel of what may work. This simple drawing is showing me problem areas-sail not contained, that could be improved. I haven't decided on the design but here is one version that could work. It has to work well in containing the sail.

The upper inverted 'Y' is fixed to a pad eye on the mast(no return line to a cleat), the 'Y' ends have small blocks. The only adjustment is in the lower line attached to a pad eye at the boom end. It runs; through-Y blocks- 2 cheek blocks to a cleat at the gooseneck. There will be enough length at the cleat to gather it to the mast.

My biggest concern is, do I even want something to take to the mast and off the sail, or is that necessary?

This main is a bear to furl at nearly 18' along the boom. I'm not too concerned with raising and lowering between the Jacks(should I be?), I can go head to wind as I usually do. What about chafe? I hate the idea of another set of lines slapping the mast at anchor.

It looks difficult to contain the foot area-aft of material but I do want to be able to dump the sail completely, and straighten it a bit when I cover(or just raise it again to sail away). This is the critical area-too far aft and it will more easily catch battens(full only at the top, the rest over sized but not full)

I was sold on the Dutchmen system but it's more than I want to add to the cost or complexity of the sail.

I intend to do a trial Lazy Jack system so I can adjust it in use. After that, I'll have a new cover built(old one is in tatters) to fit. Any advice?