Hello there. Long time occasional lurker, first time poster.
I'm part of the Planetary Content Team here at NASA Ames that partners with Google, Inc. to get content into Google Mars and Google Moon. Emily pointed me at this thread and asked if I could help.
Let me first apologize for the staleness of the Google Mars content. There are a lot of factors there that I won't go into, but I can assure you that we're working on it, and hope to have improved (near-automatic) updates from the PDS to content layers in Google Earth real soon now. However, that's an entirely different category of problem from the one you're contemplating.
I can see that you guys are working hard on getting a map solution in place, which is awesome. My group can help with that, and its one of the things on our plate for Google Mars updates (so we're gonna do it anyway), and we might as well do it sooner rather than later and get it up on a temporary server so that you can start using it, with the expectation that the overlays we provide on this server will become 'burned in' to the Google Mars basemap at the next major release.
The question is how do we go about it? There are some decisions that we have to make and I'm looking for your input here.
One of the issues is that the Victoria Crater DTM and color image are not positioned as good as they could be on the global coordinate system in Google Mars (this was one of the first HiRISE DTMs made by the USGS over three years ago). Would you favor leaving it where it is (so that existing KML that you and others have built will stay put) or should we try and do a better job of controlling its position (and the position of the nesting HiRISE b&w image, etc.) which will cause the topography and imagery to move relative to where they are now (you know, probably not by a whole lot)? Naturally this latter option will take some time because we'll want to really get it right this time and not have to do it again.
The other issue is that it is easy for my group to take the HiRISE images that reach from Victoria Crater to the rim of Endeavor, mosaic them together and get them put in place. However, there is a HiRISE stereo pair (PSP_010341_1775 & ESP_012398_1775) over the western rim of Endeavor Crater that has not yet been made into a terrain model. The quick thing is to just do a good job of mosaicking HiRISE images from the known 'good' anchor of Victoria Crater outwards. If we do this, and then a DTM of the Endeavor Rim comes along later we might find that our mosaic has wondered a bit by the time it has gotten to the rim, and we'd have to go back and correct it. So that could be pre-empted by making this DTM now, but it would take some time.
I look forward to reading your thoughts on these issues.