Seriously, the last two years are littered with the corpses of Bitcoin exchanges, wallets and trading platforms. Why would anyone send Bitcoin to a new site at this point?

Wouldn't the first priority be to establish escrow with a trusted third party, or use m-of-n transactions?

At the very least, build the site with full transparency so you can prove publicly, every 24 hours, that you control the private keys to all Bitcoins entrusted to you.

We use m of n locked contracts on our site, so you dont need to trust the exchange with bitcoin https://www.cointures.com