We are a team of developer working on a Bitcoin mixer. The method is very simple. Our customers will be sending their bitcoin, we will deliver the premixed coin to the customer. The entire process will be done within three or less blocks. We will charge a small fees for our service. The newly collected bitcoin moves to a pool and once a week we coinjoin the coins. The coinjoin coins are now ready to chunk for future premixed coin.
Let us know if we will have a business potential with the concept. We also would like to discuss the fees that will be involved in the process. We don't want to charge high, we don't want to charge less too because managing a business needs to generate profit to continue it. Let us know a balanced number that will be beneficial for both of us and potential customers.
This is funny, pre-development discussion? About what? Fees? There is nothing innovative that you offer right now and no one here is going to tell you something innovative, that's for sure. You should offer us something innovative and then ask us to discuss about that.
You also answered your question about fees, let's give people possibility to choose fees themselves like other mixers do and even if you manage to create a good mixer, zero-fee policy will generate pretty decent profit like Chipmixer had.
Come up with an innovation, market is already saturated!
Also you might be the subject of hacks and/or money laundering investigations, so to protect yourself at least from the hacks, you should use reverse proxies to host the website and keep the backend servers hidden very far away, with IP addresses that nobody knows. Better to run your own full node for broadcasting transactions than to use a third party.
If he really needs this advice of yours, then he should never run a mixer!