A slower, staged withdrawel from Sub Sahran Africa could only have improved the lot of the ordinary African.
My belief is that while decolonisation should have begun in the Fifties, it should have been a gradual process.
Stage one. Establish elected local councils and promote competant locals to run the various departments. Only keep colonial personel in position until competant locals are able to fill the posts. Higher levels of the colonial administration keep a close eye on the new bodies to ensure they are both performing their jobs satisfactoraly and without coruption.
Stage two. As above but for wider regional bodies.
Stage three. Establish an elected advisory body to work with the Colonial Govenor.
Stage four. Hand legislative control to the National Parliament with the Govenor able to Veto harmful bills after consulting the home Goverment.
Stage five. National Parliament takes control of international affairs and defence and after a short period of supervision by the former colonial power achives full independance.