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XD is low profile stable putter similar to Rhyno size, also Classic Roc (a mid, but sort of a putter and closer in design to a Rhyno).
Try a Quantum Sentinel MF (Millenium). It's a modified Cobra, very overstable mine can handle 40+mph winds at 350' ft without flipping. Shallow rim/grip, edge shaped like a Roc but smaller, wider in diameter.
Putter: Try one of the Vibram putters. I think they feel and react similar. Or a Challenger.
Just look here, http://marshallstreetdiscgolf.com/htmlpages/flightguide.html, and go feel some at your pro shop or wherever you can buy discs.
For the putter, it sounds like the Soft Focus would be right up your alley. It is a nice low profile disc with less stability than the Rhyno, but not really understable.
As for the Midrange, the Lat64 Opto Pain with a nice high dome will give you the more stability you are looking for. Don't let people talk you out of this disc, just hand pick one with a nice dome on it.
For the putter, maybe check out the Innova Wedge. Super thin profile, and (i believe) Innova's most understable putter. It's a new model that was just released this year. I can putt from up to 45 feet on a completely straight line with it, and it's by far the most successful putter I've ever tried (I prefer to putt on an annhyzer line though)
As for the midrange, when playing with a ROC, its pretty much my most overstable midrange in the bag. maybe get another ROC but get it in one of the harder plastics like the KC Pro or DX and by one that's 180g. That should help add stability...
Opto Pain with a high dome; if you can get it to turn i'll eat my hat.
Latitude 64 Spike for Putter
Discraft Hornet for Mid
Both can be purchased cheap at http://www.essentialdiscs.com