First, the high baroque time with full plenum more ore less all the way was already over for Bachs time. That is not what is necessarly needed to play Bachs organ works.
Depends on the piece. There are some that I would now do with more modest registrations but this is one that deserves, and asks for, a big and majestic sound. A concert organist like my teacher (he's played and recorded all Bach's organ works on this organ) does not hesitate to pull out a goodly battery of stops. - and never mind your ears protesting sitting are right beneath the pipes...
Next, a big organ to play on is nice. However I am sure the fuller you make the sound the less you hear the nuances in the music. Like a loud rock concert. If it is that loud, all sounds good but your ears shut up. One better practises with softer registration and plays also not almost all Bach pieces in full plenum.
Which is not at all what I am doing
Next, often big organs stand in a big church. That means unbearable strong reverb, helps also not just to improve on playing. And big churches are mostly cold, even in summer.
I think the natural reverb in this church is just perfect. In the other one I played a couple of times, that
was just awful, and unsuitable for recording anything but the real big slow pieces.
Yes, it is cold ... so what ! That's never stopped an organist. Though I could do without the cold hands, but I have them anyway these days, must be an age thing.
Yes you are one lucky geezer, having landed right away an instrument you are perfectly happy with. Make the most of it. Certainly more than adequate for practising, but for recording I would want a bit more sometimes.