Be aware that a carbon fork is probably going to be deeper at the crown. In other words the bottom of the of the crown that your tire has to clear is lower - less clearance or the fork is longer, raising the front of the bike that amount and lowering the head tube angle, slightly altering the bikes handling and pushing your position on the bike back and handlebars up.
Another alternative would be to have a local framebuilder make you a steel fork. That's fun. You get the stiffness you want, the handling you want and you get as a bonus to be able to pick the fork crown and make a statement. (Here you could see if there is a crown that is shallower and allows a bigger tire.) Braze-on choices are endless. 650B brake mounts or just threaded bosses so you can mount them. Racks, generator, fenders, a sheath for your sword, the choices go on forever.
I'd ride the fork you've got and take notes on what you would like different. Quicker or slower steering? Stiffness? Are there reasons you would like to go threadless or stay threaded? (I love that threaded allows quill stems that allow real changes of height very easily. That change can be made minutes before riding. No torque wrench required. Quill stems are almost all a lot easier to eyeball alignment with the front wheel too. I have a bike that I have two "cockpits" for. Two very different handlebar/stem/brake levers/brake calipers. Turns the bike into a completely different ride in 5 minutes. But if you wanted say to be able to use tow or three stems with the same bars, shifters and brakes, threadless would make that far easier.)
Take your time and enjoy the process! This can be a lot of fun.
Ben