Ok so your squat you are able to add weight every workout? If so then you don't need the light day. As for your bench press have you tryed micro plates? I don't see why you couldn't bench press with this set up bellow.
Monday
Bench 5x5 advanced novice/ early intermediate last set needs to be very hard just like when you was doing 3x5
Squat 3x5 new pr novice
Cleans 5x3
Wednesday
Overhead press 3x5
Squat 3x5 new pr novice
Chins 3x failure
Friday
Bench press 1x5 new pr advanced novice/ early intermediate
Squat 3x5 new pr novice
Deadlift 1x5 new pr
Remember, what is a novice? The ablity to recover workout to workout. If you can do this you don't need a light day. You state your bench is not progessing. This is a set up for advance novice bencher who recovers in 75 hours to at most 96. Intermediate is around 96 to 120 hours. The longer the recovery the less heavy you can go. That is the only reason why people have light days.