Issue Type permission restrictions to work log

Presently there is a global permission to turn time tracking on or off.

In turn this is driven by Time tracking permissions accessed via a permission scheme.

I think there should be a further capabilty to configure which types of issues can have time logged (and in combination with some sort of user/group/role privilege).

We have created a number of different issue types and with time tracking on, users with generic log work capabilties can log time to any one of these issue types.

We would like to be further restrict this based on issue type.