What would change
The cost of a specialization change would drop from 15 reputation points to 0.
How it benefits us
Dropping the price to 0 would allow people with highest bloodlines to make the switch to another offense easier after spending the 120 reps required to do so, rather than spending an additional 15 reps. In addition, it would also be easier to check the tags of the other offense variants of each bloodline jutsu, allowing players to make more informed choices whenever one is thinking of changing offense. It also reduces general confusion.
Why it matters
With the most recent changes to highest bloodlines, and how the offenses for them are chosen, specialization has become extremely devalued, now only being used to simply change the tags on BL jutsu from one offense to another. In cases where a specialization has already been chosen, a player that opts into an offense change often finds themselves with a mismatched specialization, causing their bloodline jutsu to be of the wrong offense. They would require another 15 reps spent, on top of the 120 reps they spend on an offense change, making the true cost of an offense change become 135 reps.
Game staff might want people to spend the extra 15 reps, alternatively the offense change can be increased to 135 reps while making specialization change free. This will still be a quality of life change giving players less hassle.