This sounds great. You guys are amazing!
I'm a bit skeptical regarding the security tokens thing, though. There's a bunch of things you won't get around even if you're a decentralized exchange, and I'd rather not see steem-engine be shut down by the SEC or another regulator.
If you trade actual securities, meaning the security tokens themselves, you're likely to be considered an MTF and be regulated like one. This would impose a lot of reporting duties as well as processes against market manipulation etc
If you plan to trade pegged security tokens, you'll need a regulated custodian to keep the actual ones.
You will have to perform KYC on all your traders, and probably need to filter out traders who aren't eligible to trade a particular asset.
And some more similar stuff.
Not saying "don't do it", just saying "be careful". Being "decentralized" doesn't mean there's no owner or accountable (and prosecutable) person.
If you're aware of the stuff I wrote and you got it under control already, even better :-)
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