UVA likes to see that you took the most challenging curriculum available at your school, and were able to handle it (i.e., got good grades in the hardest available courses) and work your way to the top of your class. That’s the single most important thing. It predicts better than anything else what kind of college student you are likely to be. So if you’re in the top 10% or so of your graduating class, taking all (or most) of the Honors and AP courses available to you, then don’t worry about “3.45.” Your transcript is far more (and more important) than your GPA.
The other thing to remember is that UVA is 2/3 Virginia residents, 1/3 OOS. But they receive WAY more applications for the fewer OOS seats - it’s really, Really competitive for OOS applicants. This year they had 21,706 OOS applicants competing for 1,225 seats, compared with only 9,147 residents applying for 2,450 in-state seats. So even though an OOS applicant might have higher grades and test scores and such (and they do, on average) than an average Virginia resident applicant, that might not be enough for them to get admitted.
http://uvaapplication.blogspot.com/2015/03/unofficial-uva19-admission-statistics.html
Either way, you don’t want to be in the situation, “I know my numbers are weak, but I hope my ECs make up for that.” They get more than enough applications with solid numbers AND solid ECs. You instead need to be in the position, “I know my numbers show I’m qualified, and my EC’s distinguish me from the rest of the pack.”