What happens to IFR departures off your airport NOT on a SID/SDR?
An SID is designed to provide, among other things, a known profile that a. simplifies the job of separating aircraft on climb-out and b. provides terrain clearance.
In my experience, in unregulated airspace you can probably (forgive me) get away with "less" control of the departure. SIDs may still be utilised, but under the conditions of the ATS available in Class F &G airspace the pilot is responsible for terrrain clearance. Therefore, IMHO, if granted a non-standard departure ROC issues would be left to you in the cockpit. I would, however, still expect the pilot to climb to a level that provided IFR en-route terrain clearance. I cannot allocate a heading until above a safe level (as this is construed as issuing a vector and re-introduces terrain clearance issues)... but we get around this by using the phrases such as "own navigation" or "direct"
Subject to the above... I can/will approve a
requested non-standard departure profile, subject to workload, as long as it does not conflict with other traffic. If there are no beacons, radials or DME requirements, I would consider the departure profile ended when steady on heading and either level or passing any given level.
PS: Be careful when reading any replies on this thread, and remember to take into account that local procedures may not apply where you are flying....
PPS: We have some pilots who insist on asking for a "non-standard SID"... bit like the pilot I once heard asking for an "actual PFL"?