I'm swapping out forks on my '06 rush hour pro. The stock house carbon/aluminum fork is straight (not sure of rake). I'm getting a curved reynolds ouzo pro (all carbon) w/ 43 rake for it, both to lighten the bike up and to make the bike look cooler
All my riding is commuting/urban, will the handling/feel be significantly different?

Depends on the rake of the fork you currently have. It probably has less rake than the fork you're looking to replace it with and it's worth being aware of that In a good amount of cases on track bikes increasing the rake makes the bike alot less stable.

i am in the process of putting on a Forte Axis carbon road fork on my Pista, Ill let you know how i turns out this evening

I'm mostly concerned about road riding/handling differences, no plans for the velodrome just yet.

From the catalog link above ('07 actually)(thanks!), my existing head tube angle is 74^, fork offset is 40mm. The fork I'm considering is standard road 43mm. So my trail dimension will decrease by 3mm?

not exactly but yeah it'll decrease some. 3mm probably won't make very much of a difference though so you're probably good.

When I had my rush hour I swapped out to a 43mm rake fork after a crash that bent the original one. I could tell it was a different fork, but it wasn't a negative change, just a tiny bit more twitchy. It'll be worth it for the ride qualities of the Ouzo Pro.

found this link to compute trail:https://www.kreuzotter.de/english/elenk.htm
I'm getting about ~2cm of trail loss, given an outside tire size of ~28".

It's about 2-3mm, not centimeters. That's just about nothing really, it's possible you could see a bigger difference just by switching tire sizes than between those two forks.

Trust me, you're good