I don't know exactly where these signal controllers are used.

But they certainly should detect when a carriageway is completely
empty and therefore does not need to remain on green while there is
traffic waiting at other junctions.

Also there should be a maximum time anyone should have to wait at a
red signal, and in my opinion this should usually be no more than 45
seconds.

In addition, signals should be synchronised with other signals so that
if travelling along a main road (in the North of London that means A1,
A41, A10 and A503, just 4 roads, can't be that difficult surely), you
will generally come up with a succession of green lights, i.e. each
light should turn green for you as you approach.