I really like this idea, making the gas nonspeculative and one way to do is make the utility token a stable coin. On 3Speak we have the same issue, "RC's" for posting to the IPFS storage system for videos. We separated the utility token, stripped it of everything but its utility, and are doing sorta of a hybrid between how Hive works with RC's and how GAS works with Neo.

But I believe the idea of pagging the utility token as a stable coin.