As long as we're talking about adding core features ...
Most programming languages use backslash as a delimiter delimiter. Maybe this would work for MW as well?
If you want to use \ as an escape character you have to replace all literal uses of \ with \, which destroys backwards compatibility. It might be worth it anyway (we're not going to be able to fix everything without some problems occurring somewhere), of course. It does mean that people are going to get very confused when they try and use backslashes without knowing they have to escape them.