What inseam pants do you wear? I'm a 34. Also, how big do your quads measure? They may be bigger than you think but look small because they are so long. Remember, Arnold, the greatest bber ever and was one of the most massive bbers ever in his era (second only to the much smoother Sergio and Arnold was much more developed than Louie), had 28" quads. So 25" is pretty big for a non pro or recreational lifter. I think quads are too big now and distracts from functional ability. 30+ quads for a guy 5'10" is the norm now.
Arnold did say he included a lot of front squats. Front squats and Hack squats are good if Back squats are difficult for what ever reason.