All website mixers are liable to fold and submit all backend data to authorities when jammed and under pressure, hence making manual mixing/tumbler much more secured and anonymous.
And what stops you from submitted all your data to authorities, or selling it to the highest/multiple bidders? If manual mixing is so much better, why do we need to send our coins to you? Why not just do it ourselves?
What is your method(s) for mixing the coins?
How long will it take?
What are you going to charge?
How can you ensure the outputs will be "anonymous" as you claim?
How many coins are you currently holding?
Can you sign some messages from a handful of addresses to show you have adequate starting funds?
Given that you are a brand new and complete untrusted account, as Royse777 asks, what will your collateral be and who is going to hold it?
You're going to have to do better than just "Send me your coins and I'll totally send you some clean ones back". No one is going to believe that.