Sounds like you've made some good choices.
As for the power supply, the more voltage, the better. Gecko recommends 4x to 20x the motor's rated voltage, up to a max of 80 volts. An unregulated supply is fine.
You'll have to decide how you want to drive your router.
Precision ground ballscrews are the best, but out of my price range.
Rolled ballscrews are more economical, but generally less accurate.
Precision acme rods would also be a fair choice, depending on your budget.
Let's have a look at your drawings, always nice to see a new build.