heistotron

I'm not sure what the chances are of getting off a wait-list from a BME PhD Program in normal times, and how that might change at current times. Hopefully things will work out soon enough - one of my friends that was wait-list at a top 20 bioengineering program was told that he would be notified about final wait-list decisions by early April.

This is great! I do want to note though, that for a lot of schools outside the top 5, accepted GPA doesn't necessarily mean enrolled GPA (which is usually lower). Understandably, the strongest candidates (usually with very high GPAs) will be admitted at a lot of programs, but are less likely to commit if it's not a UC Berkeley/Caltech/MIT etc.
Thus, even schools in the lower top 10 e.g. UT Austin may see a drop between accepted GPA and enrolled GPA, as candidates who are not as strong and without as much offers are more likely to commit. In their 2017-2018 data, UT Austin's average accepted GPA was a 3.88, but had an enrolled GPA of 3.83. Source: https://gradschool.utexas.edu/admissions/where-to-begin/admissions-and-enrollment-statistics
Mind you, they're not big drops to begin with at a top 10 program like UT Austin, but less competitive programs are more likely to see bigger differences between average and enrolled GPAs. What this means is, if you see an average accepted GPA that makes you hesitate to apply to a program, more often than not your chances aren't as bad as you think. Finally, people that post results + stats on Gradcafe also heavily skew towards the most competitive/highest achievers and may not fully represent the applicant pool. Still, there are some exceptions like MIT in the provided link with an average GPA that's pretty much in line with official stats.

I can't help but think places like Columbia/UPenn would be great in terms of tissue engineering research. They both have strong BME programs and their proximity to medical campuses only help (from my understanding a lot of faculty are funded by NIH grants).

Stats are Ok but there are much bigger questions. What are your research interests? Are you aiming for masters or PhD programs? You definitely have very reasonable odds at chemical engineering programs ranked 50-100 and I would apply to a few higher ranked ones as well. But most important thing is to figure out what you actually want to work on and that's not something people can easily recommend without you providing more info.