There's a reason to sit in the high numbered rows. Plenty of bin space if you get on early.
I know. You're also closer to the bathrooms which is good if you have to go, but bad if there's a line and you're in the aisle seat, or if there's a foul odor. Also, last-minute assignments, i.e. middle seats, go front to back, so you have a better chance of scoring an empty middle in the back rows.
But the overheads also fill up first in the back, so if you're running late for whatever reason and can't make the first call, you're screwed. Heck, on our last trip we almost got screwed on our Houston-Phoenix US Air leg and we were sitting in the very front, i.e. first, where there's normally plenty of overhead space. Unfortunately the C terminal Fuddrucker's was particularly slow and we hadn't allotted enough time (or rather allotted too much time enjoying free drinks and wifi at the PC), so by the time we ran to the gate, they were already boarding the last of coach and had started gate-checking all carry-on bags too big for the underseat. Fortunately there's a bit more room under the first class seats and I know better than to book bulkhead, so we were able to squeeze my backpack and small roller and Janna's backpack and purse all under the seats in front of us.
OK, that's user error, but there are times when a flight delay means late boarding and potential gate-checking of delicate items, which I've literally seen kicked and run into by carts and tossed 6 feet up to the baggage door only to miss and fall back on the tarmac. What that would do to a laptop, or housing, or camera strobe, or even a regulator, I shudder to think.