[Kevin Leonard]

In the same vein as what Ty and Nathan suggested, you don't need that much clearance between your retracted traction wheel and the ground, and you could use a lot more mechanical advantage to make actuation easier, so what if you mounted a shorter piston right above the traction wheel. This increases the lever arm and decreases the throw for both faster actuation and more mechanical advantage.

Play around with different setups like that and see what seems to be the best setup you can in that configuration.

As far as being cantilevered octocanum modules go, I feel like it should be fine, as long as it's well-put together, and so is the rest of the robot (including bumpers). But I have no experience with it.