CGEpro. If my budget were 5K I'd get this or the losmandy G-11, and then figure out the rest from there. Wouldn't even mess around actually. A used CGE might be better if you are setting up each time you go out, think it's a bit easier to assemble.
Losmandy has it's new Gemini 2 out which will have most of the features people are looking for on a Software Bisque model without the price tag. The Gemini 2 is out and is basically beta at best so problems you may have seen my be related to that. The G11 Gemini 1 was a pretty solid mount. Sold my Celestrons mounts to get a Titan and a G11. Mygemini 2 is on the way but it's going to be 30-60 days before the software is totally ironed out for astrophotograpy.
I was reading through this thread and I agree with people about getting a beefier mount. The difference between the CGEM and the CGEM DX is the tripod, which comes from the CGE Pro, which brings it in line for capacity with the older CGE (45lbs I believe). The capacity of the CGE Pro in 90lbs.
Before you buy the 10" astrograph from Orion ask around about it, it's a rather large scope and I think on a CGEM DX you might be pushing the mount beyond it's limit, which ends up causing a lot of frustration.
Now don't get me wrong you can photograph with a setup like that, heck I started with a Meade 10" SCT on an LXD75 mount, it was way past the mounts limit but I was able to get some images :) But once I upgraded to a CGE Pro it was a world of difference and the very first image I took with the pro was light years beyond anything I obtained with my old setup.
A DSLR can give you some pretty nice images (even if it's not modified) while a decent CCD starts at around $2K. I currently use a Canon XSi for all my imaging and while I would like to upgrade to a CCD I'm still pleased with what I obtain with the Canon.
As for the optics... you'll end up going through several of those if you end up like most of us in this hobby :) So just start with what you have. On a mount like a CGE Pro (or better) you could take subs (individual images) well over 20 minutes using something like an 80mm scope (or I think you mentioned a 150mm as well).
It may not seem like your getting much by dumping everything on a mount as it's only one piece of equipment, but it's deffinitely worth it in the long run as the mount is the single most important piece of equipment you can own for imaging.