I've been on QC for a couple years now. Even with all our new features, i still don't see any futures, forex, or options Alpha Streams for sale. I also don't see many people pubishing their ideas on the community hear. As QC grows, it may be beneficial to encourage the user base to branch out into other asset classes.
In addition, your annual returns are capped at a certain level with stocks. There is zero leverage. Leverage is how you make money.  The most you can find is 3x Leveraged ETFs. 

Forex 25 to 50x 

Futures 100x

Options 25-50x 
I realize the education may be lacking , since its so easy to pick up stocks (buy and hold).
The simplist explanation of leverage is a $1 move in an asset would generate a $10 or even $100 profit or loss in your holding of that asset. 
My personal goal is to have an algo running with at least 4 asset classes. crypto, stock/options, forex, futures.
I did create a futures algo but ran into issues with Interactive Brokers API. Because of this i never created the AlphaStream.  i just started forex so i haven't seen any real gains. My stock/options i trade manually on my brokerage because i haven't found a good options algo strategy.