This is more a minor clarification and helpful Rule. All players are free to create Bloodlines/Clans and Abilities. If you want to make them server-wide however it is required that you find two other players willing to make one of your clan with you, until then it will be qualified as a 'Special Ability' for your character. For more information on Costs please read the Token Cost Section of the Forums, Every character may have only ONE Clan/Bloodline. However multiple special abilities are allowed.
When it Comes to Custom Dojutsu, it is highly unlikely to be approved. it isn't impossible, but it will require alot of RP, hardwork, and convincing as well as Originally as to how it formed, what it does, and how it isnt a copy of the Byakugan, Sharingan, Rinnegan, ext.
Hybrid Kekkai Genkai Abilities are -RARE- if two Dojutsu users have a child, the child will 99/100 times have one or the other Dojutsu. Only 1/100 of those RARE Dojutsu couples will have a hybrid. Hybrid Abilities are NEVER below 400 tokens, they are strong people, and getting them is not easy, but its possible. Same for Non-Dojutsu Kekkai Genkai, again possible, but it will not be easy to get.
Dojutsu implants, are posible but limited. As well, they are required to have a submitted story, as well as several IC events of Gaining it after the story is then approved by the DM team.