Legs Lagging: Frequency of Lifts

Whatup Bros. I ve been training hard for about four years now...training correctly for the past 2 and a half. I have made great progress in weight and strength, gaining about 45 pounds while maintaining a bodyfat under 9%. However, I have found that my legs simply have not responded as well as the rest of my body. Oddly enough, they are definitely the part that I work hardest. My workouts now consist of backsquats for 5 sets, 3 sets of 10 and 2 sets of six, followed by four sets of leg press in the 8-10 rep range. My hammies I sometimes hit the same day as quads, sometimes the next, with stiff legged deads followed by machine work (leg curls). Calves I try to hit three times a week, low rep, short wait in between sets. I don't particularly understand the reasons why my legs dont respond, and I would like to think that while not genetically gifted I am not cursed. My basic question is what have you guys encountered as your most effective lower body mass program? Is two times a week enough, or should I go three? Higher reps, lower reps? Anything You guys can help me out with will be appreciated.
As of right now I am 22 years old, 5-11, 205, 8 % bf. Quads are only 25 inches,calves 16. My chest is 48 inches, biceps close to eighteen, and I am desperate to avoid looking like a top. Thanks bros. - R

I forgot to mention that I also include three sets of leg extensions and three of hack squats on quad day. Thanks guys. - R

Legs are hard to give another person advise on. Most people do okay with working out one day per week. Calf are another hard part for people also. The muscles in the calf and thigh are a little different than the muscles in the arms and chest so you have to work them differently to get them to grow. For me, my thighs work well at once every 5 days with high rep and moderate weight. I also have a knee problem I have to keep an eye on. My calfs do well with once every 3 or 4 days with high reps and moderate weight. My upper body muscles work best once every 2 or 3 days with moderate reps and high weight. You really have to figure out what works best for you.