kristooph,
it's a very good design, but for an indie survival/crafting game, not for a tennis game, even if it's an indie one !

Same for your menu, you should use a tennis (or at least a sport) related texture : for example, some clay or grass, or even blue concrete.
EDIT:for TE, I see something slightly futuristic/modern style, with pure & clear design.
And about logo, look Ubisoft logo :
https://www.google.com/search?q=ubisoft ... =isch&sa=X ; it's not that simple (there are several shapes within each other, shadow gradients), but the whole thing is still pure & very clear to read (while your TE is simple but not clear to read nor pure)... Note: you could replace "pure" by "natural", "well flowing design", like in "the eyes will flow well reading the details of the logo"