That sloop (single mast) version looks right to me on a boat of this size, and I think it would give you the best results. One sheet, one halyard, one yard hauling parrel, one luff hauling parrel - just four running lines to manage, and the latter two just need a tweak.
The trick to balance when running, even when broad-reaching, is to ease the sheet right out until the uppermost sheeted batten is absolutely athwartships. Get the boom as far out as possible too. My method is to ease the sheet out until the top sheeted batten is athwartships, then overhaul the sheet to ease the boom further out. This pulls the top batten back in a little, so I then ease the sheet further until it is once again athwartships. I might do that two or three times until I am satisfied the sail is as squared out as possible, with the least amount of twist in it. My last boat, Arion, was very well-mannered downwind, but with the sail squared out like this, I could drive the boat as hard as I liked under self-steering and never round up or broach.
If I ever find myself converting a wide-beamed, moderate displacement, traditional 10m boat (my ideal cruiser) to junk rig, then I will try out my schooner idea, which is to have the largest mainsail possible, with the main mast as far forward as I can get it, and a very small, stoutly rigged foresail. This would allow me to reef the mainsail going to windward and leave the foresail flying, thus moving the balance of the rig forward. This really powers up traditional-type boats to windward in strong winds. For broad reaching and running, the main would be squared right out, as described above, and the foresail sheeted in flat.
Another advantage of this dream boat's rig is that it would be much more convenient to sail off the anchor with just the mainsail hoisted. I do it on my sloop rigs, but get annoyed by the luff of the sail triying to swat me off the foredeck.