Re: questions about the level up features on the site.

You can read about it more on the official blog post here Leveled Up! | Royal Road

Basically it's just a mechanism to gamify interactions on the site, just for fun! Higher levels unlocked custom border, which usually is better than the previous one. Fun fact: Currently there is only one member who has unlocked the highest level border: The Mighty Zethuron. It's true! You can check it yourself from the Member List!

Reputation is basically Royal Road's "Like" mechanism. The interesting thing about Reputations is if you have many reputations you can give more reputations to others. 

To be honest, I was hooked by this game mechanism and became much more active because of the Levels and Reputations. Previously I was just a silent reader, and now I tried to comment and write reviews whenever I can.

Hope this helps