Yeah, all coins in one request that would be great. As of now I have to request one coin at a time with custom hashrate and this hits "429 Too many requests" error sometimes. What's the server policy btw?
Also, is it possible to include the default calculator's hashrate into each coin's JSON? This way we could download the whole bunch in one setting and recalculate custom hashrates locally by simple multiplier. This could alleviate server stress as well.
Currently rate limit stands at 120prm. I might set a new limit and start selling unlimited access, no final thoughts yet.
What you are proposing with default hashrate would work for coins with very big nethash, but not for small ones.
If you are adding lets say 20% of current nethash then the rewards will not increase linearly, as your addition would significantly raise difficulty.