Currently, everything that is farmed / digged / produced / build / repaired etc. is done through projects. A project has a fixed duration (perhaps with repetition), can have a number of participants, etc. Well, you know all about this

The advantages for digging are: 1) slightly more realistic; 2) clean up of projects list (no massive projects anymore); 3) easier to keep working as long as possible; 4) easier to see how fast you are producing. Disadvantages might be: 1) no way of forcing your employees to deliver their gathered goods to you - they now voluntarily have to hand over their goods from their inventory to you. I can't see any other disadvantages

For repairs it would definitely be better, imo, since 1) it removes the bug of being able to stop deterioration by adding all your old tools to projects you don't actually work on; 2) it allows more easily for repairing that you can stop halfway if you suddenly need the tool or weapon; 3) it's more realistic; 4) it allows for bigger things to be repaired - e.g. buildings should not vanish into a project temporarily

Note that if this were to be implemented, old projects could still be finished, of course, but you wouldn't be able to start new digging or repairing projects.