Just did a leg workout myself. It included... oh, let me find a list somewhere so I can copy & paste...

Balance Lunges, Calf-raise Squats, Super Skaters, Wall Squats, Step Back Lunges, Alternating Side Lunges, Single-leg Wall Squats, Deadlift Squats, Three-way Lunge with Kick, Sneaky Lunges, Chair Salutations, Toe Roll Iso-Lunges, Groucho Walk, Calf Raises, 80/20 Speed Squats.

Plus some back exercises (pullups) mixed in there a few times.

Do a bunch of different things. Your legs are designed to work in multiple directions (which cycling definitely doesn't do).