>>1182471The front quick release is not the wheel axle - the quick release goes inside the axle itself and just compresses the fork on the hub.
The through-axle you have on the rear is the actual axle so that's why it's so much bigger.
Through-axle is considered much better (much stiffer, less prone to failure, easier to operate I guess if a bit slower) but conventional quick releases are absolutely okay as well (at least if they're of the internal cam type on top - I've had the external cam type QRs slip on my MTB).