To be honest, the cleanest way to report out on these is to separate out the different task types. As you've discovered, State values and labels differ from table to table, so you'll never have a very clean State reporting mechanism across all task types. While not ideal, there is some value in having them separated - each task type can have a different process involved, and thus the states should be slightly different to reflect what makes the most sense for that process (ex. Incidents are always going to have different state options from RITMs).
If you absolutely must have in a single report, you could try something like this, but I wouldn't recommend it, as it's clunky and takes a bit of patience to set up and maintain as new task types need to be added to the report:
