this post about dealing with simple combat maneuvers while reading stuff on the super helpful OSR Links to Wisdom site. I think this is a great solution to the problem of keeping combat interesting without adding complex rules or breaking the system. Basically you can declare any special move you want to try and then you roll an normal attack - if you get a critical hit you pull it off. If you get a normal hit then the defender gets to decide to take the hit or take the effect of your special move. If the attack is simply an attempt to force someone away from something or towards something they don't know about, then the defender would probably let it succeed. On the other hand, if the attack is to disarm or a pin or a throw, then they will likely take the damage instead. I think this is interesting and could add some interesting choices to a combat without causing too many headaches.
Now in Beacon which is d20 and where you presumably have skills that could cover these maneuvers, the questions should be why would you do this instead of just using skills and stat vs a DC check and why a critical hit instead of a DC value. Well obviously this rule is intended to allow for combat actions that are too effective to be regular skill checks or combat rolls, maneuvers would probably be abused to replace regular combat rolls if they were predictable to pull off. By placing the choice on the target's plate you avoid the abusive portion of this and by making a critical hit the only way to take away that choice you are setting the bar pretty high for success (target choice or 5%) but without a penalty for attempting it. Also we can't forget the natural inclination here is to think - oh only a 5% chance for this to work, but in actuality it's based on the maneuver - sure a killer hip throw into the volcano will only have a 5% chance to succeed, but something more subtle like a flank or a push back probably will succeed because the target will opt for it over potential damage - especially if the target is wounded.