Yes, you can cut off any parts that aren't part of your vision for this plant, as much or as little as you want so it matches the shape you imagine it could have. Keep in mind that new branches will likely start forming where you cut. Over the next few years, you may decide to do a series of cuts, so that at any particular time it doesn't look pruned, or you might prefer to have a flush of fresh new foliage across the whole plant.
Ficus elastica does well in full sun outside, so when the light is significantly lower, it will have a more relaxed, leaning habit, usually leaning toward the light if not rotated often. There's nothing wrong with that, but if you would prefer a more upright appearance, and you have another spot with more light, you could move it, rotate often if you're aiming for symmetry, though that could take a few years to cultivate from what looks like a more flat, fan-shaped current appearance. It looks very healthy and cutting parts off will not hurt it.
You can stick the removed pieces back into this same pot, or a new pot to take root and keep growing. There's no guarantee that they will but no harm in trying if you want. Remove enough leaves so that there is enough naked stem to stick all the way to the bottom of the existing pot or a new pot, at least 6".
Watch out for white latex sap when you cut into this plant. If you lay newspaper on the floor under the cut point, you'll avoid making a stain on the floor. The sap may also run down the trunk and stain if not rinsed with a squirt bottle.
IMO, trying to separate roots would be more trouble than reward.
There are many pics of F. elastica & cultivars in the plant database on this site, especially pics of prune spots and the resulting new branches.
https://garden.org/plants/sear...
