I think that since we're including a duration and cool down part in jutsus. That there should be details on what is expected for durations and cooldown for the specifric ranks to make it better.
Basically I see it as that the higher the duration and the rank the higher the cool down. So maybe something like:
Then, for every one or two addition to duration a jutsu has then the cool down will be one post higher.
No jutsus should be less than 2 posts cool down so as that it prevents spam. And then it cna further be mentioned that if you have a specialty in something then the cool downs will be one less to further make people want to get specialities.
Basically I see it as that the higher the duration and the rank the higher the cool down. So maybe something like:
- D-Rank: 2 posts
- C-Rank: 3 posts
- B-Rank: 4 posts
- A-Rank: 5 posts
- S-Rank: 6 posts
Then, for every one or two addition to duration a jutsu has then the cool down will be one post higher.
No jutsus should be less than 2 posts cool down so as that it prevents spam. And then it cna further be mentioned that if you have a specialty in something then the cool downs will be one less to further make people want to get specialities.