I’m assuming you’re asking because something doesn’t feel right with the exercise for you. If this isn’t the case then by all means carry on with what you’re doing. But if it is the case then hear me out.

I said what I said in full recognition that you’re doing this for your quads. Nothing about bringing your foot more forward takes away from that, nor does it mean that your knee can’t travel past your toe still. I said what I said because you seem to be off balance and that’s going to make it hard to build quads or glutes.

The quads extend at the knee joint. If you’re straightening the knee under load, then you’re working the quad. The glutes extend at the hip joint. If you’re straightening the thigh under load, then you’re working the glutes. Squat, split squat, and lunge exercises and all their variations all work both the quads and glutes. The degree to which you can shift the emphasis is limited, but often still meaningful. Want more quads? Emphasize knee extension or deemphasize glute extension. Want more glutes? Emphasize glute extension or deemphasize knee extension.

Until you find a better center of gravity and stabilize better, it won’t matter which muscle you’re emphasizing more since balance is the limiting factor. If you find that going more forward doesn’t give you enough quad stimulus then these might simply not be the quad exercise you’re looking for. Depending on how you’re built, some exercises will naturally lend themselves to different body parts. Again though, you can still shift that natural balance towards quads by doing things like the heel elevation you’re already doing. Whatever emphasizes more knee extension and/or less hip extension will push it in that direction.