Do you have a multimeter?
Red LEDs will have higher resistance current limiting resistors (on many cases) so moving to almost any other LED will result in it not using as much power as it could. If you also desolder the resistors and replace them with lower valued ones you'll end up with brighter LEDs overall.
That said, blue / white LEDs usually have a higher luminous efficacy rating, and will produce more lumens per watt. you will probably be okay just desoldering them and soldering in new ones.