They should try and make role specific cars that are somehow better at their rolls like goal keeper etc or select your role at start that makes it better.
That way we can have a new meta every few months and game stays fresh.
The game have multiple layers of skills which is required. It can stay fresh even with current scenario. Giving one car advantage over the other is not good since it will impact the game negatively.
In current scenario, anyone can become goal keeper and anyone can switch from offensive to defensive and vice versa. If you fix one person as goalie, other team might attack knowing this beforehand. So element of surprise will be hampered if we fix one player to do some specific thing.
As for the multiple skills required those are in following order:
1. Making goals
2. Defending goals being a goal keeper
3. Defending goals NOT being a goal keeper
4. Dribbling ball and having a better control on it in general
Even when and if you master above skills, then comes the "Ariel" skills. Even touching the ball mid air is a challenge, making goals is a distant skill.
With so much to practice and master, the game have too much to offer. I on the other hand drive only in my BTTF DeLorean, so that I don't have to worry about customization (which I think is just shenanigans).
And with the 3 new maps coming, RL will only go better. Developers like EA and Ubisoft should learn something from Psyonix!
Plus almost ALL games support them