I agree on your point about ETH and NEO. But I dont think ETH should be at a much lower marketcap, but instead I would see NEO at about 20 to 50% of the marketcap of ETH (that would be NEO at 2x to 10x from current price).
And I think GAS will have a demand driven price (like ETH), which will push GAS price over the price of NEO in the long run. While NEO will be the governing token issuing GAS to its holders.