A loaded 321 on a 3 hour flight has extremely high V speeds. 170 plus knots is very common. I haven't flown a 737-900 but I would guess their V speeds are high as well, but maybe not that high.
A 737-900ER needs significantly more runway then a A321 with the same payload under the same conditions. It has to to with installed engine power/ acceleration, the more fuel the 737 needs to carry (sfc) and the restricted maximum rotation angle at lift-off for the 737-900ER. The long tail, short MLG limits this more then at the A321.
I found videos (that prove nothing) of the two types taking off from the same runway with the same destination, from the same airline under similar conditions.
737-900ER
SKY Airlines Boeing 737-900ER (!) takeoff at kjevik - YouTube
A321
Sky Airlines. A321. Takeoff. Kjevik - YouTube
Take your stopwatch, look at the required runway and rotation angles. Proves nothing but gives an impression.
Think again. Add about 25 to those figures for something more realistic and typical operating weights. The A321 is at about the limit of the type's design parameters.
Dan, all I can find is:
http://knology.net/~stirmac/POHfiles...0320%20POH.pdf
Cant find it for the 737-900ER
Any increase in mass over the 321 will need a major redesign and a new wing - and possibly a lot of recertification.
Yes, that's what I included in the concept. A long bigger wing/MLG for higher MTOW, more fuel and lower wing loading. IMO the A320 wingbox could be beefed up for 10% higher loads. It done before.