Just got the equipment necessary for Brew in a Bag, with an 8 gal Kettle from Brewer Best with it thermometer and so. I've got a high profile burner at a Chinese store with 80K BTUs on it specs hahaha.
Usually I do my cooling with a copper inmersion wort chiller and also, put my kettle on a cold bath, at the same time.
For my fermentation process I leave my fermentator at 22 degrees for 4 days and during the stability process, I increase 2 degrees the temperature.
Just experience on witbiers. My first two batches were crappy, with a water taste and no much alcohol. The practice made my witbier better on the following batches. I'm interested on Stouts with coffee brew.