NMoasis said: Re the depth: I'm looking at the separate stalks/trunks emerging from the soil and wondering if they are in fact forks, in which case we should be able to see the common single trunk from which they all originate, or if they are indeed separate trunks of separate plants or emerging directly from the roots. If the bark underneath if the same bark as above, it's too deep and you should lower the soil level to the root flare. That one little stub would annoy me but perhaps you should avoid further pruning for now.
Many succulent growers consider MG cactus & succulent mix too peaty and water-retentive for excellent drainage, but opinions vary. Jades are pretty easygoing.
Generally, red on leaves is a stress reaction. Based on your description and seeing the pic, I'd say to lack of water unless it's suddenly getting direct sun through that northern window (could happen early morning or late afternoon at this time of year), but I wouldn't worry about it.
Can you show a photo of the whole plant?