Bah at the routine = sleeping through. Your baby doesn't sleep through the night cause she's a baby! LOL!
I agree with Sherie, if what you're doing is working for you, keep doing it!
I guess if you were fed up with the night waking, places like Tressillian would recommend a routine. But even they don't expect 5mo babies to sleep through the night. Plus they would want to start your baby on solids. You might find that when you do start solids you have a little more structure to your day... We've only really found our days are more structured now that Natty's on three solid meals.