A Red/Ice Dragon mission of some type is in competition for a launch in 2018. There was a NASA labs conference a week ago in Houston where Red Dragon, Ice Dragon and Red Dragon-MSL (using the Mars Science Laboratory re-entry and atmospheric trajectory) were discussed at great length.
The conference went well for the Dragon proposals as the interest was high for the idea of a cheap, mass producible lander that could deliver at least a metric ton of experiments; 3x-4x the current capability, and maybe more.
Another advantage for Dragon is that it's massively overbuilt for the mission; it's designed for 1 atmosphere pressurization, but for Mars it won't need that margin. As a result they can turn the metal fabricators loose to cut & weld in recessed boxes in its hull to hold multiple rovers. Add an extensible ramp, winch, and a pop-off panel for each and you're in business.
Want to do a Mars sample return mission? Put a pop-off panel where the docking adapter goes at the top and a big tube down the center of Dragon with a rocket in it. Let the rovers grab the samples, then a robot arm retrieves them for placement in the return vehicle. When it's full launch it from the tube submarine-style. The attached image is pretty blurry, it's a video frame grab off a projector, but it should give you the general ideal. This was
one of the proposals at the conference.
If the SuperDraco abort & landing thrusters deliver anywhere near the performance (120,000 lbf of axial thrust) and throttle-ability (5-7% to 100%) they are expected to it's going to be a compelling option.