Now before I explain, I know Orichimaru is in the Akatsuki but in the series he was not really part of the group. In both the anime and the manga it is hinted and I believe even stated that he only joined to get closer to Itachi. So, back to the main topic, the three Sanin or you could just say sage character. These include Jiraya, Tsunade, Orochi and maybe Kabuto with Dragon Sage but that is up to staff. What would the req be from Jiraya and Tsunade? Well simple, Jiraya is represented by a Hidden Mist clan that uses Toad Bullet and Toad Oil (The name escapes me) and Tsunade is a Senju already but is a medical ninja. The scrolls for the Sanin would be their respective sage mode. These modes would give a boost to speed and possible increase melee damage by 1 heart. Though this also means a heavy cooldown, there could also be a specific jutsu for each char. Just something I thought of and this idea is just a suggestion and not set in stone.
Thank you for the suggestion, but I have no plans of adding character roles right now. There is a clan based off of Jiraiya called Gamanoabura in Hidden Leaf. There is a clan based off of Orochimaru in Hidden Sound called Shiroihebi. And yes, Senju Clan. which Tsunade is apart of in the anime/manga. We have more than 30 choices for characters to go for right now, many of which require major development and tuning for their clans, setups, and character jutsu. I need to prioritize improving the quality of what we have now, and I think that it would be out of prioritization to create more character positions.