I think you can safely repot it now as it will certainly be several weeks until any hard freezes.
Regarding styling, the main thing to know is that they are analogous to spruce - cut back to a bud + cut back around now will induce back buds that will be apparent by spring and may even occur on needle-less old wood (e.g., trunk). Don't repot if you prune off much of the new growth. It is most important to keep a vigorous canopy.
You can wire and position branches now without too much sappy/gooey trouble. Do it first, then repot or wait until spring to repot. Repotting and subsequently wiring is generally not a good thing to do.
A fundamental of styling is to frame the most interesting thing (point of interest) with foliage. For example, I think the bark on subalpine fir is the most attractive thing about the species. The bark is always best low on the trunks. Hence, you want low branches hanging down, positioned sorta like you would have your arms and hands if you were trying to draw attention to your denims. Were the lines of your trunks bizarrely wandering around, you might consider literati, but this material simply doesn't have that character.
Start by deciding on the front (view). You want the best compromise of things - fewest flaws, most good things such as nebari, bark on the trunk, trunk movement, and branching. Trunks that come from the ground at an angle, rather than straight up tend to be more attractive. You don't want a branch coming straight out of the front (a so-called eye poker). Then having done this, you will want the top of the tree to be coming forward. It seems so trite, but this key 'subtlety' often makes a big difference. Trunks that lean away tend to feel unfriendly (like recoiling in horror from me). You might simply prop up the pot to achieve this 'bowing to the viewer' and proceed with wiring and positioning branches. Then repot when you are done, putting the tree(s) back into the pot (or another) in that attitude.
It should be lots of fun.
Enjoy