Worth noting it's also the first rocket using electric fuel pumps instead of turbopumps.

To optimize the weight they also drop the batteries once they get empty.

The first stage seems to be very vertical compared to other launches; any explanation why?

Small rockets suffer more from drag than bigger ones, because there is more frontal area per mass. Thus it makes sense to get out of the atmosphere very directly. It's also why small rockets look very skinny.

Or maybe it's related to the launch range.

Or something else. These are just guesses.