RJ, your set up is working fairly well, but what is the Isc of the panels? My two 100s have Isc of 6.3 (actual) (6.4 published, with 5% tolerance) and I do get that 12.6a when pointed in full sun showing on the Trimetric at the batteries.
Proportionately, 190/200 x 12.6 = 11.97. If 10.4 is the best you get, then perhaps your panel Iscs are lower. If so, are the Vocs in the 22v range instead of 21v range?--that's something I have noticed lately. OR, you are losing 1.5a somewhere.
Today we too had a cloudy morning with clearing in the afternoon.
What a pleasure to be able to twirl the contraption into the sun when it came out, and make hay while the sun shines! :)