Well, As we all know reversing is a major field in security,Hence more of reversing challenges not only with software cracking but with malwares and elf binaries and exploitations should be given.Reversing exploitation challenges should be introduced as these are the realistic topics and to be worked on.
All 3 of the ones provided were way too easy as well. I had them solved within about an hour or less (all 3). Plus by some of what I was seeing in the call stack... I don't think they were written very well.
I am however having difficulty in other challenge groups where I am not so familiar.