What is it about malleability that is such a big problem? In the almost 7 years of Bitcoin's existence, I am only aware of two "companies" that have claimed to have been negatively affected by malleability, and I believe both of them are/were lying (I know for sure that at least one of them is lying).

I would think that a more common sense fix to the sighashing "problem" would be to limit the number of SigOps allowed in a transaction, as I do not think there are many "business reasons" why any given transaction would ever need to have a large number of SigOps.