When do I get more Power Tokens?

Solution 1:

The correct term is "Power Tokens", and according to the game's wiki you will have 12 tokens of various types at most (there are actually tokens which are better than yellow tokens). You gain your first (blue) token at level 7 with an additional token at each consecutive level until level 14, and then it gets a bit more complex, so just go ahead and follow the link for the specifics.

Seeing how you have more than 6 inventory slots with each item taking up two tokens at most, you will never be able to have all your items require two tokens.

For completeness' sake, here is the picture of the table contained in the link I provided: