Aside from the fact that what you're saying isn't actually true (Rubio has consistently been lauded for his defense), he's got some of the best passing, playmaking, and court vision in the entire league.
There's a reason why Rubio's agents are pushing for a max deal (which they will certainly not get, but he's still going to get paid).
Your apparent bias against Rubio doesn't change the fact that he's a starting quality point guard and his contract is not terrible at all. $4.3 million for Rubio is a steal considering he is easily going to make more than double that when he's up for his next contract. The qualifying option is irrelevant since he won't be signing that because he'll be signing a new deal.
Is he horrific at shooting? Yeah... which is why you surround him with shooters to whom he can facilitate, since that's his primary job as a point guard. Something he happens to be amazing at.