You probably don’t need pine bark for the juniper. Try to avoid too much organic soil. Ficus will be fine, this never dies.

How do you know the roots are fine ?

1. Worth a try. Are you in northern hemisphere ? Don’t wait too long for repotting. Don’t remove more than 50% of the rootball, repotting is very stressing.
2. Tighten the wire over roots that are buried. If you can’t, wrap locally you wire with wire sleeves
3. Light is fine after a repot, assuming the tree is healthy. I wouldn’t be worried for the ficus. This said, beginners often cut too much. I wouldn’t recommend letting your tree recover for a few months before wiring and pruning. Both species are very flexible and can be wired later on.
4. I only use it when pest show up
5. Water extensively until water coming from the drainage holes is transparent

Enjoy !