This is pretty cool. It faciliates the use of what I've seen as a number of sore omissions from bash. I dislike the "why aren't you using a real language" mentality - if we can make bash better, why not do it?
Why not? Because building on a solid foundation makes for more reliable and robust programs. Things like Shellshock and the Valve bash bug that wiped out all your files demonstrate that the shell scripting languages have fundamental design flaws which make bugs more likely than in other languages.
I wouldn't suggest writing user-facing shell scripts, and bugs (even big ones) happen with other languages all the time. I don't want to see large pieces of software written entirely in bash, but scripting where it's useful is fine with me.
Because missing something is only one way that something can suck. Not everything can be fixed through additive processes.