H.K.
I asked my 10 year old (will be 11 on Thursday) about Pump It Up and he said "No way!" But he is a pretty mature acting 10 year old.
On of the best boy birthdays we have ever thrown is a "Fear Factor" birthday. Remember that tv show? We created all kinds of challanges, divided the guests up into teams and they competed...it was great fun!
Last year the 10 year old had a "ball party". We wrote invitations on plastic balls, gave away balls as the goody bags and you guessed it played with many different kinds of balls at the party (held at the local park). The guys really had fun with the big yoga balls on the tennis court. It turned into some kind of extreme dodge ball game.
This year he is taking a few friends go-cart racing at Speed Street Indoor Track on 67th and Bell Rd.
Have you looked into paint-ball? That was high on my son's list as well. There is always Lazer Tag too.
A friend of mine did an "combat party". The boys all brought their air soft or Nerf guns and just played war in her huge backyard. She set up two base camps on opposite sides of the yard with boxes marked "top secret" and the boys had to battle and plan missions to retrieve them.
I haven't been to the build a car place but it seems a bit young for a 10 year old...
Good luck deciding and planning!