There is a small business class lounge after pre clearance, its nothing special, so you would want to maximise your time in the first lounge, which means in my experience the lounge after pre clearance will be full by the time you get there, so don't expect to get a seat.

I don't remember any priority lanes for pre clearance, but my last time was pre Covid, however I do remember they did tell me in the first lounge when it was the latest possible time to go to pre clearance.