I think that all battles are a horrendous experience for the common soldier – I imagine which battle is irrelevant, as you are engaged in your own personal battle for survival.
I think many of the battles mentioned were horrific – Monte Cassino was mentioned and my grandfather fought there and had would not talk about it; he was injured with shrapnel and evacuated out.
Interestingly, he would think his brother had the hardest ‘battle’ of the war, even though he did not do much fighting, he was a POW with the Japanese. One of my grandfather’s memories was going to meet his young kid brother at the docks on the south coast of England and he did not recognize the ‘old man’ who met him.
Gary, the original poster, also mentioned ‘soldier’. I think being on an Atlantic Convoy (Artic Convoy, Pacific etc) or Bomber Command (USAF) would have been equally tough given the casualty numbers.
If I had to opt for a worse battle I suspect it would be on the Eastern Front / Far East simply because of the additional ‘battle’ of the elements. Whether it be winter in Stalingrad or suffering malaria in monsoon in Burma
Cheers
Gazza