Wish you only good luck.
How we can prove you that we are not scam? What do you think?
By not keeping your hands on people's faith. Legit ICOs are a "one-step" procedure because once the funds are distributed across the blockchain, no single person can control it any more. That's the main point of blockchain technology, that it's trustless. In order to achieve this state, ALL legit ICOs run like this:
1. Collect the money
2. Emit the coins (in one step)
3. Optionally, burn the coins that haven been sold.
Result: No way for the creator to scam, except by abandoning the project, in which case someone else could continue development.
You are failing on even two points, 2 and 3. You are only collecting money. But then you don't emit the coins in one step, but partially while it's already traded on exchanges (first way for you to scam). And, you also said you won't burn the unclaimed coins. Even worse, it will probably be more than 50% of all coins in a PoS system, which is total death to the concept of being trustless or decentralized. So, second way for you to scam. Almost a proof because you're selling something that doesn't really qualify as a "crypto currency" because it's centrally controlled by you, and always has been since its creation.
And of course, being completely intransparent and "we will only answer that question to you privately on Slack", no Block explorer, total supply is secret (??) etc. does not help improving the situation.
I mean you said you would not make a new chain. So what exactly is going to be launched then, that isn't running already? 
