Of course Revolution is weaker than Imperial Age if you have the resources to afford going Imperial. It is also why it is cheaper. But Revolution is not designed to be played during hours, it is designed as a risky strategy for 1v1 to end the game quickly. In 1v1 vs a human player you never go Imperial anyway. I always found and still find Revolution fine as it is now. Don't give Revolution a purpose that it does not have (kind of a 2nd Imperial Age).

also there're no idea to gather resources when in revolution, causing low change to train some units.....

Pretty sure the Revolution is basically a Hail Mary. Like, you don't just use it as an alternative to aging up. Use it when you have a bunch of villagers and want to sack somebody.