Eh? More legroom? Leg room is determined by the airline, not the plane.

If there were fewer doors there would me more seats, and the weight of the seat, passenger, and luggage would far outweigh the weight saving on the door.

And no, you ain't getting more legroom.

Can you elaborate how having more legroom and less doors makes a aircraft go faster?

An airplane with four doors instead of eight would weigh less so the plane may fly a little faster. Legroom shouldn't affect the speed.

I don’t think weight affects cruise speeds a whole lot, as I understand.

At least, not enough to make your flight measurably shorter.

https://aviation.stackexchange.com/questions/47369/how-is-th...

No, the limit of airplane speed is the speed of sound, as you get very close to that aerodynamics changes greatly. While you can make a plane go faster it is rarely done.

So will an airplane with 5% less luggage or fuel. Go figure.