If the key light is getting to bright on their face, making them squint, or causing dramatic shadows then the first thing you should do is add a silk screen and not a scrim. A scrim will lower the intensity, but it will remain dramatic. Try putting a silk up to troubleshoot this issue first, then try to use a reflector and turn the light away from the subject. That way you will only get diffused and reflected light on the subject's face. This will help the three point lighting set up be a little more practical for tight locations.