I wish they would eliminate "gate checking" for carryon bags over the limit, and make the people who come to the gate trying to sneak over-sized bags onto the plane go back to check-in and check them. Of course they would miss the flight; that would stop trying to sneak on over-sized bag real quickly.
Or at least do what one or more of the low-cost airlines does and charge more for gate checking than for check-in bag checking. Right now there is no penalty for attempting to sneak on over-sized bags. If you check the bag at check-in, they charge you a fee, but if you try to sneak it on the plane and have to gate check it, it's free.
We noticed that some of the under the seat space had a seat leg smack in the middle
Last time I flew, I had a "bulkhead" seat, so there was no under-the-seat space for my personal item. The FA took it and put it in the overhead bin.
if you are tall you have to put you feet somewhere.
That's why they have Economy Plus.