[DoctorOetker]

I would love to try trading as a hobby with a little side money, but I would abhor a hobby that reduces to effectively buying the trader-feel-good experience, where you're essentially sponsoring incumbents as a fanboy chipping in his pocket money.

What I would require from a trading platform:

1) decentralized and permissionless 2) provably fair trading

With 'provably fair trading' I mean the protocol should be such that I can prove you are not simply held captive by an intermediary, regardless in what shape or form. It should also be fair with respect to latency.

For example consider a trading market where token X can be exchanged for token Y and vice versa. Each holder of X demands her minimum of Y per X, and each holder of Y demands his minimum of X per Y. What if everyone salty hashed their demands, and pays the market contract (proportional to how much they will actually be allowed to trade) to register their salted hash. When the round has closed, people reveal their salt and plaintext, and the incompatible trading offers get their money back (minus a usage fee perhaps). The compatible ones can have their trades go through at the rate of 'total compatible X offered' to 'total compatible Y offered' (or some variation thereof, say rewarding those that helped close the gap). In this way there is no high frequency trading, and you could have a family of such markets operating at different timescales...