2. I really only think a ball valve is needed if you're going to be pumping the wort. If you don't have a ball valve then you're kind of forced to use an auto siphon to transfer wort after whirlpool and chilling, which means that you have an opportunity to get cleaner wort transfered if you're careful. Whereas if you have a ball valve and are impatient like me, you tend to suck up some break material and hops.
I was recently perusing my old brewing logs. There was a period in the late nineties where almost every batch that I brewed was fantastic. I wanted to know what I did different during that period. What I realized is that I used an unmodified Vollrath 38.5-quart stainless steel stockpot as my kettle. I had briefly left the hobby and sold all of my gear in 1998; however, it did not take long before I realized that doing so was a mistake. The kettle that I sold was a St. Pat's of Texas modified Vollrath 38.5-quart stainless steel stockpot. It had a bulkhead that consisted of a Swagelok fitting that was welded directly to the kettle, which resulted in a low-profile design. For some reason, I was unable to purchase another St. Pat's kettle, so I went to racking out of an off-the-shelf Vollrath stockpot.
Here are a couple of recent photos of my old St. Pat's kettle that I obtained from the brewer who now owns it:
Anyway, getting back to the non-modified kettle. Well, what I discovered was that racking out of the kettle was the major difference between the good beer that I made earlier with the St. Pat's kettle and the great beer that I made during this period. Racking immersion chilled wort resulted in bright cast-out wort, which, in turn, resulted in cleaner tasting beer. I eventually replaced the non-modified Vollrath stockpot with a first-generation Polar Ware brew kettle with welded fittings and a false bottom (I have always used whole hops). Reviewing my notes revealed that there was a small drop in beer quality when I did so.