Hmmm. If this not going to bed till 9 has been consistent for more than a week or so, then yeah, maybe it's time to cut the nap. And that sucks. My daughter napped until she was 5. My son stopped napping at 2. He might have been 2.5, but it was still way too early for me!
For us, my son was just wound up. He was happy to play and be busy all day long but when it was night, he just wanted to go to bed. So for a while he was asleep by 7:30ish each night. That lasted for a couple years. He's 6 now and is still asleep by 8 every night. He can stay awake longer if it's some kind of occasion and I allow them to be up later, but otherwise he's perfectly happy to crawl into bed and usually falls asleep within 10 minutes.
So, my point is...I think she's probably ready. And although it sounds like it's terrible to give it up, and it kind of is, it will make your life easier! I personally find it much more relaxing to just put my kids to bed and have the evening to myself and my husband.