Better backward support for vba macros, it's ridiculous to have to write a new macro for each version of excel in a company.
As long as you’re using functionality that exists in previous versions, macros should be backward compatible.
If you have a specific problem, please feel free to post it on UserVoice or on answers.microsoft.com.
Kenneth Barber commented
It sounds to me like this is your fault. If your macro is not backwards compatible, then you are using features that are specific to later versions of Excel. Since you know that your company has different versions of Excel, write your macros to work with the oldest version. If the oldest version is too old, try giving IT a talking to. I don't think that Microsoft will make their older Excel versions forwards compatible just to run your new macros.