And don't forget standard leg curls. It's important to work antagonistic muscle groups.
As Clint said, try plyometrics. I'm a huge believer in this. It'll build strength, explosiveness (power), and will improve cardio. It's also a great way to break past the plateau of a stagnant routine.
I would like to do regular deadlifts but there's not many straight bars in the gym I go to, and I'm not a fan of dumbell deadlifts. The stiff legged deadlifts I do with dumbells and that feels great for my hamstrings.
Maybe what I'm getting at is how many excersizes should I be doing for legs? 3 and I'm out doesn't seem like much but I definatly do feel it and I work up a good sweat doing it.
Seems like you got some pretty good replies already. I'm just wondering, how many reps/sets are you doing?
4 sets of each. Reps depends on the weight. If I'm going heavy it'd be around 8-10. I try to do a lot but sometimes I'll cap out at like 12. I just wonder if I'm hitting everything with 3 excersizes even though I'm feeling it.
I would maybe do hack squats for your inner/lower quads. If you're doing calve raiises, you've got them covered. Really squats can cover almost everything if you do them with proper form. You should always do a bit of direct hamstring work though. What you're doing sounds good. Eventually you'll hit a plateau and then you should think about doing more high volume for awhile, but right now it sounds like you're building fast twitch muscle fibers pretty well with high intensity/low volume.