Hi B.-
I have struggled with this question myself. My son (Dane) is now just over 4 mos & at first he was taking late naps or sometimes not, but still didn't go down to bed until rather later at night, around 10-11 pm. That was all before we implemented the Ferber method for sleep training. Now we have a good routine down every night & he goes down anywhere between 6:30 & 7pm. He usually does not take a late afternoon nap though, so by this time, he is really exhausted & giving him his bath puts him into sleep mode. I have usually nursed him about an hour before we start the routine. We also still swaddle him when he goes down, b/c those hands are just wild when he's crying it out. It is working well for us, b/c he is sleeping a good 8-9 hr stretch!
I think in the beginning you have to feed more often & if you are nursing, feed on demand, so that makes for a later bedtime, at least it did in our home. I would let him go to bed a little later though, if he would take an afternoon nap.
I am also 32 & a SAHM. I don't know if you happen to be local to my area, but if so & you ever want to get the kids together to play & some FT-mommy-swapping-stories, I'd be up for it! I live in Port Richey.
Hope this helps!
K.