[@pkken] There isn't no reason. As an academy and genin. I want you to have 1 nature release. A chuunin can have 2. A jounin 2 or more but they are limited too. 
Though that doesn't mean in the roleplay you can't learn a nature technique as a Genin. So Genin in the roleplay with permission and training can learn new natures.
As Reflection said you could work towards the Kekkei Genkai. There isn't no point on having it.