Congrats man! I’m an undergrad at Hopkins and hope to have the awesome decision you have one day but here’s my opinion :)!
You should probably go to where you feel you’ll fit in the best. Firstly, you said there are more faculty members at JHU you’re interested in working with and since you’ll most likely be working with these individuals for the next 3 to 5 years of your life you should consider this heavily. Each program has their own caveats and like you said you may prefer the more quantitative analysis and mathematical modeling at Caltech over the more bio-focused projects at JHU. It only makes sense to go where you’re going to be learning what interests you the most decreasing your chance of attrition and perhaps speeding up your program completion.
I’m from the LA area and personally Pasadena is one of my favorite places on earth. Baltimore has some nice things going on from what I’ve experienced but I would rather spend my young adult years in SoCal over Bmore. Feel free to PM me any specific questions that I may be able to answer. Best of luck deciding!