I would say follow your gut. If you think you'll be happy there and you enjoyed what you saw of the program, go for it! I am in a similar situation (with other factors in play), but I was given full funding and a fellowship from UC Riverside. I haven't heard back from other schools yet, but UCR reached out to me and every interaction I've had with them has been positive and inspiring. There are several things to consider, though. I'm not sure how much of this you've already done, but I can tell you some of the reasons I chose UCR:
1. Someone mentioned this earlier, but it seems that if a school really wants you and thinks you're a good fit, they probably would have contacted you by now. Personally I would prefer a school who chose me right away as opposed to putting me on a wait list. I do realize not everyone is lucky enough to have found that school that is a good match mutually, but it seems like you have with UVA.
2. Feedback from current grad students. Have you contacted them and asked them about the program? How have their interactions been with the advisors and professors, etc.? Do they feel like they have support?
3. The TA position (if applicable). UCR has a coordinator who works with all grad student TAs, plus everything is planned for them: the rubrics, the lessons, everything. So all I would have to do is give the lessons and do the grading. This was so important to me because I want to be able to have sufficient time to devote to my studies.
4. Interactions with advisors/professors. Have they responded to your concerns? Do you sense that they care about your success?
5. You already did this when you chose where to apply, but reconsider the similarities in your research interests. What school has faculty that match up well with your potential research topics?
These were some of my main concerns, but obviously everyone has different preferences. Think about what is important to you in a grad program. Another thing that helped me decide was I considered what I would do if those other schools offered me acceptances. Would I even accept? I decided I wouldn't because UCR feels like the best match for me.
That being said, you do have until April 15th. There is no rush to accept. You could wait a week or two, see if anyone else gets back to you, and see if you still consider UVA as your top choice. Good luck!