Moving it to a spot with the most bright light you have available (if not already) would help it become more vigorous. Pruning removes that which is causing the plant to not look like you want it to, and doesn't need to be done at 1 time. You could do it gradually over a year or 2, so your plant doesn't have a time when it has no foliage at all, without which it can't photosynthesize.
Does the pot have a drain hole? If not, I'd move it to one that does as soon as practical. Unglazed clay pots can help reduce the risk of rotting roots because they are porous and roots can access much more oxygen in them.
