You've got to have it.....
.....to teach it.
If you want to instruct to basic PPL level then the IMC rating is not required and probably would not hinder your chances of employment too much from what's been said on here.
My ME/IR (JAA) is currently lapsed and has caused me no difficulties work wise whatsoever. If I were to move on to CPL or CRI(ME) or IR teaching then it would probably be advantageous to revalidate the IR and ME ratings.
As for the IMC - do it. Regardless of whether you need it for employment or not it will improve your understanding of flying and also improve your flying skills (keeping within tolerances etc.....). Those who say it's redundant are 4 years too early.....and it will help you when you come to do the IR anyway.
HTH
Duchess