Regarding geriatrics and electives: You have the option to push geriatrics to the start of 4th year and do a selective instead in a field you wouldn't normally be exposed to (options include things like ophtho, ENT, EM, PM&R, rad onc, urology, pathology, etc). The major downside is that then you have to do geriatrics at the start of 4th year which is a common time to do away rotations. For things like surgical subs (and anesthesia), you don't necessarily need to do this because you have time at the end of your surgery rotation you use to pick a subspecialty you're interested in. Same for medicine (you pick a medical subspecialty).
Not all are in the Bronx, but most are. Some are further out like New Rochelle or West Nyack. Car service/shuttles are still provided to all sites.
I'm an M2 so can't comment on rotations yet but my clinical experiences so far (through the Intro to Clinical Medicine class) have all been great.
All med schools have their pros and cons. Overall I am am personally very happy with Einstein and think it's the right fit for me. Admin can be frustrating at times, but I do think they genuinely care about students and try their best to listen to and address our concerns.
In terms of involvement, most students are involved M1 with the free clinic. It's a great way to gain more clinical exposure as a first year.
There are tons of clubs, you can check here:
einstein.yu.edu/education/student-affairs/student-activities/involvement/clubs
Step 1 dedicated is like 7 weeks (at least that's what it is this year) but most people only take 5 or so and take a week or two of vacation before M3