Contax and Olympus made great SLRs. If you go Contax, don't get an AX. Go for one of the RTS models or an RX. Olympus has made some of the best lenses in all of photographic history, but so have all the major companies. Minolta, Pentax, Canon and Nikon also all have lenses that are without peers. Each company's top SLR lenses are the best. These days with computers designing everything, there is little way that lenses can get better aside from making tolerances tighter but then possibly diminishing the quality of handling or features like autofocus. Personally, I'd go for a Nikon F4, but that's just because I loved mine and thought it was the greatest SLR ever made. Still do.
Just because you have an issue with parallax doesn't mean you give up on rangefinders. The RF camera can serve as a lightweight, quiet tool for just walking around. If you need to do closer than .7 meters, then a macro lens on an SLR is the best way to go. Same goes for telephoto. You just can't shoot anything longer than 135mm because of the accuracy of the rangefinders and because the lenses don't exist, for the most part.
I'm in this same boat right now, contemplating what dSLR I will get to compliment my current rangefinder kit. If I need to shoot macro or telephoto I'm going to need an SLR. For everything in between, I love the rangefinders.
Phil Forrest