Found this range of motors with a back up / holding brake http://fluidpowersolutions.ca/pdf/Parker%20Motor%20LSHT%20DF%20Series%20Brake%20Motor.pdf
They do not have a case drain as many motors that do, often have anti vacuum valves incorporated, it is though possible to flange mount an anti vac (cavitation) valve on the motor, reducing pipework.

I also made a study of the older Struck hyd machines, these use an external mech cart brake in the drive, & seem to use a directional valve with 'per spool' overpressure relief valves built into it (so taking care of the pressure spikes when using motors on a cyl spool) Their motors do seem to have inbuilt case drain & anti vac.
They also use a dual gear pump, the first one dedicated to the travel drive. The second one connected to the equipment spool block, BUT this block has 'power beyond' - thus there is the option to inject this power beyond flow into the travel feed via a tee, non return valve, & a dump valve leading back to the tank. This gives a higher speed option (which disappears if an equipment spool lever is operated) & when not selected the power beyond flow goes directly to the tank via the dump valve. (the N.R. valve prevents the main travel flow short circuiting though the dump valve) Just a couple of ideas for the Cadtrac guys