I've never had a problem with 20-40m/h runs. If I did a single loop of my current trading run every other time that I play, I would have more than enough credits to support most of my chars. Not to mention that I trade with 3800 cargo space.
Mining on the other hand should be boosted to at least match, if not be better than trading. Currently, using a joint miner/trader effort, my friend and I can make around 8m each per run. Don't ask me how long each run takes though.
Also, increasing the yield of mining would be nice. Ideally, one should be able to mine enough ore to fill up a freelancing trader (max 3800 cargo) in the time that it takes the trader to deliver the ore to the destination and return for more.