7.30pm is a good bedtime, if you are going to change it I'd push later - 7.30pm bedtime routine for 8pm sleep for example. But making it later may mean adjusting the timings of daytime naps to accommodate.
It is worth bearing in mind that 11h overnight sleep is average for a baby/toddler having naps. That's an average too - so the range of 10h-12h are perfectly normal.
Therefore a 7.30pm sleep time could give you 5.30am wake up. I wouldn't consider wake up "early" unless it's closer to 9h over night - so 4.30am for a 7.30pm bedtime.
Some things you could try:
A late evening "reset" might help. When you go to bed, wake baby. Do a nappy change to ensure a proper wake up and feed. Then resettle. The idea is that come early morning, when sleep is lighter, that she she is a little more comfortable in her nappy and a little less hungry/thirsty
Moving daytime naps to make bedtime later. It's perfectly reasonable for a 16 month old to still be having 2 naps a day. Limiting the AM nap helps keep the PM nap established. A later afternoon nap (say 2-4pm) will assist with making bedtime later.
Converse to above, his might be a sign that she is ready to move to 1-nap days. The idea is to power through the morning and push naptime after lunch. I'd then probably give a few weeks over to lengthening naptime. Cosleeping for naps can help with this. A 12pm - 3pm / 4pm would be ideal.
Another option is to just accept early morning cosleeping. Loads of families do this. Just being baby in with you when she wakes in order to get an extra hour or so sleep.
One final thing - it helps to have the child happy to be awake in her cot. So working on going from fully awake to asleep in the cot helps with this. Also having a (safe) toy or two in there. I also don't rush to get toddler if she wakes and isnt crying. Have her get used to being awake in her cot and not upset.