It's possible to suppress a timer's output signal by using an AND gate, but the suppressed signal still causes redstone updates and the gate takes up additional space. It would be nice if the timer could be disabled entirely while the redstone signal on one of the sides is high (or low; personally, I would prefer either low or configurable). I found the current design to be awkward on several occasions and Etho seemed to find it unintuitive in one of his HermitPack episodes.

I'm willing to take a shot at designing and implementing this if you're interested. (and will make sure to compile it with Gradle this time, not just with Eclipse :P)

Feel free but be sure to make it compatible with current behaviour. i.e. by default it should behave exactly like it does now as many builds depend on that

Do you have a document or world file which contains all of the test cases you use for each block? It would be safer and faster for me to follow an existing test plan than to try to come up with a comprehensive list of cases by myself.