That dash cooldown mechanic is one of the things we were unsure about, it felt necessary at the time but I agree that it makes the controls a little bit clunky. Thanks for the feedback!
Maybe the cooldown makes sense, but you should then only allow roling without spacebar. So while still in cooldown, check if the player is trying to do another dash, by holding the spacebar and if so, don't move at all. So an attempted dash ist not converted to a roll instead.