PILLOWS! You must take a couple of pillows, in cases you'll recognise so they don't get mixed up with the hospital ones. They are great for propping you up in bed for breastfeeding, maybe during labour too (I certainly found them helpful) and are nicer than the hospital ones if you stay overnight.
You should be aware that although you hope you'll be home in 6-8 hours after birth, you might have to stay in a night or two if there are complications, so I'd always overpack, just in case.
If there's a chance you and the baby will stay in longer than one night, you will need more than 2 babygros, believe me! 
OK, I was in for 8 nights after DS, so that was extreme, but you may find that your baby wets through the babygros almost every change (until you get the hang of the nappies, but sometimes newborn babies just don't fit the newborn nappies very well). I had to keep sending DH out for more babygros! Also nappies.
As a rule, you tend to be given a few maternity pads, some nappies (like, 5) and you're put in those disposable knickers with a pad after you've showered after the birth. (This was my experience anyway, in the JR.) That will last you half a day to a day.
Front-opening nightie is nice if you plan to breastfeed, and even if not, it's great for skin-to-skin without being entirely naked on the postnatal ward!
I did use my cds, but a lot of people find they just forget to. I completely forgot to use any massage oils, and I brought a lot.
Camera with lots of memory is a must, so is a charged phone. Most maternity wards now let you use your phone.
As you might have gathered, I over-packed (and boy, was I glad, because I went in 2 days before EDD for a check-up, was admitted with hypertension and stayed in until 8 days after the birth!) but I did find home comforts very - comforting! I had some favourite photos in one of those A4 clear plastic envelopes, which went on my locker and were nice to look at when I was feeling a bit down. You labour more effectively if you feel safe and homely, so try to think of something you can bring in which would help with that, like a cosy pillow. And ask if you can dim the lights in your labour room!