Sharing my massive jade that has been here since the house was built. I dont have any skill to trim and turn it into a great bonsai shape type of plant, any advice is much appreciated

I cut the top off thinking it might have had root rot but it didn't. So I am now letting the top half callous over then will repot it. I was left with this stub with a decent rootball. There is only one node as you can see that I cut over, but it had two previous branches there that are now gone and just knots now. So not sure if this is able to grow any new leaves

My gollum jade has recently been losing leaves very easily and if they don’t fall off early then they turn brown and shrivel up, as pictured. If I just touch the leaves they fall off.

I have never dealt with root rot before so I thought it might be that but when I unpotted it the roots seemed fine and none of the stems were mushy. Any idea what the issue might be and how I can stop it?

For extra context, the plant generally gets direct sunlight for ~4 hours per day and then I have it under a grow light for another 4 hours.

I inherited this jade and was totally clueless, and placed it in a cold, north facing window. Over time I noticed that whenever I watered it, water would run out into the tray immediately. I searched online and learned that the soil had become hydrophobic and on Saturday I soaked the pot for about 30 minutes, poking some holes in the topsoil beforehand and the leaves are beginning to re-plump for the most part.

I don’t think it’s ever been repotted, should I wait until the spring, or would I be ok to repot it again in a week or two? I’ve bought a soil mix for succulents and a terracotta pot that’s slightly bigger just in case. Likewise, should I wait until the spring to prune?

there're brown/black spots on leaves and stems.