No UST, period. Anything in the pipeline you can't wait for. You might want to look at the NoTubes FR rims, if you have 32h hubs.
Yes 29" bikes in 99% of situation will send less shock to the arms/shoulders. Fork are longer (slightly flexier, when using same tubing), but more importantly : small bumps are ridden up over a longer stretch by 29". The 29" tire arrives are the bump (imagine a curb) sooner, and finishes it later. Smaller peak loads on the handlebars.
Some comfortable but affordable forks are offered by : On-One, Jenson/Zion, and other might add more. wider tires will help of course, and you'll likely be running 29" tires at a few psi lower than you would similar 26" tires.
Something that kept me from upgrading my (reall harsh, but light and strong) Surly fork, has been going to Jones H-Bars. Ideal for SS'ing : wide with some cush, and an aero position for spinning the flats. I'd suggest a combo of the above mentionned forks with an H-bar, for a lower price of a Reba and cheap broomstick. Even the Carbon On-One fork is not too expensive, and should be quite soft too. Do tell the builder which fork you'll be running, there's a huge difference in fork geometry between offerings. The On-One offering, with it's 47mm offset, should make designing the ideal bike easier for your builder.
Good news : you can sell the Fox.
Yes 29" bikes in 99% of situation will send less shock to the arms/shoulders. Fork are longer (slightly flexier, when using same tubing), but more importantly : small bumps are ridden up over a longer stretch by 29". The 29" tire arrives are the bump (imagine a curb) sooner, and finishes it later. Smaller peak loads on the handlebars.
Some comfortable but affordable forks are offered by : On-One, Jenson/Zion, and other might add more. wider tires will help of course, and you'll likely be running 29" tires at a few psi lower than you would similar 26" tires.
Something that kept me from upgrading my (reall harsh, but light and strong) Surly fork, has been going to Jones H-Bars. Ideal for SS'ing : wide with some cush, and an aero position for spinning the flats. I'd suggest a combo of the above mentionned forks with an H-bar, for a lower price of a Reba and cheap broomstick. Even the Carbon On-One fork is not too expensive, and should be quite soft too. Do tell the builder which fork you'll be running, there's a huge difference in fork geometry between offerings. The On-One offering, with it's 47mm offset, should make designing the ideal bike easier for your builder.
Good news : you can sell the Fox.
. You will need to run a much lower pressure than what is recommended. I am not 100% sure but the suggested settings are the same as the 26" fork. 
