This is a great bot. There is really just one worry I do have. If too many people get their hands on such a great bot like this, it may cause a problem to the referral program. Think about it. If the referral program is being abused heavily, Riot will come with a counter plan and make the worse possible to happen to us. They may even totally take away the Referral-a-Friend program.
Just a thought. I suggest a monthly donation requirement or something to cut down the number of users. I am not supportive of what other bot developer (not gonna name him) had done. But this will eliminate some leechers and provide a safety net for the referral program. Also, I know that you developers will be able to focus more on the Refboo.st when you do not have a concern for money. The little money made from this bot can ease some financial stress. Lastly, I believe that when you guys do a wonderful job at this, you should deserve more than just simple thanks. Donation is shown as a true gratitude.