You do not list the pitch of your roof or the building orientation. I just finished my 7.5 kw system on an 8/12 pitch and it was, hmmm, difficult as I don't bend to those positions easily any longer. My orientation is 190* and the flush mount Ironridge hardware was excellent. I say that after having been in the solar business back in the late 70's during the thermal days and I built a lot of custom racks. They all worked, but the Ir system was a revelation. I do not have the space for ground mount. If I did, I likely would have gone ground simply for access. If there is a definition of diminishing returns it is me in my 70's continuing to go up on that roof for service. So, pitch, orientation of the building and shading? Flush or stand-off on the building? For a ground mount, will you consider elevating them for storage beneath? That would seem to offset the advantage of ground, but that would depend upon your lay-out. I am fighting the wireless issue myself. I bought a Ubiquiti Nanostation system but am still considering getting a hard wire out there...which I would prefer. I tend to fix electronic issues with a hammer. Taht is a personal problem of course but seems to be the way it is. Looking forward to hearing how things progress for you