It already supports barb fishing? You just type "Use-rod" and select powerfishing...
The reason why I suggest a short wait time is not to make it inefficient, but to reduce the likelihood of being banned (especially at long play times) since the action is way too fast for a human to perfectly do eevry single time.
But i understand, working for free is not something most people like doing lol.
Some suggestions so make the script less detectable:
Add a random (short) wait time after a fishing spot disappears or your inventory fills up.
Add a random (~3 seconds) wait time after clicking on a fishing spot to allow it to walk there if it is far (like the glitch we keep getting for two specific barbarian fishing spots).