My current build is 19/21. 6 PS, 6 IF, 7 ATH, and 7 WM. Level 32. I am close to 33 which will pump my str up to 21.
I wear low-medium armor (total armor weight is 14.8). I do not ever carry a backup weapon, every bit of weight just slows me down too much. I suggest playing a pike-user as a support character.
If you are looking for a 31 and under build. I love the 15/24 build, it was my bread and butter forever. Recently switched to a more STR leaning build because honestly I did not need to be so fast, 7ATH was enough to keep up with my heavily armored teammates.
It is my firmest belief that pikemen should NEVER carry a backup. Our entire purpose is support, every bit of weight added on removes our ability to go to and help our teammates as fast as possible. Having a build that sacrifices points into 1h just for the use of a backup weapon is abhorrent to me.