Welcome to the forum, Tom.
Streets & Trips has some quirks, built up over two decades of continual development. It was not originally designed as a navigation package, so the navigation features are a bit bolt-on and unoptimized, although they're (slowly) getting better.
There are several mispronunciations in the text-to-speech engine. "Us" (as in "We") is another common one, for US highways. No known easy workarounds. Hopefully fixed in next version.
Navigation view and dynamic turn view will control zoom levels. If you do not want this to happen, then you should not use those modes.
If you uncheck "Arrange map view" and disable the whole tree, then S&T will not arrange the map for you. The controls are disabled because they're ignored. The map then stays at whatever settings you used -- it will not scroll or zoom in/out.
If you keep it checked, then you're telling S&T to manage your map for you -- it has to do something, either keeping position centered, or arranging zoom levels too. Therefore, it doesn't really make sense to turn off anything when "Arrange map view" is on, because you've explicitly told S&T that you want it to control your map view.
POI text only shows up when you're zoomed in. If you're only interested in one specific POI (like a hotel), the best way to handle it is to add a pushpin with a text bubble so it stands out. Pushpins show up at all zoom levels, and they take on the same font size as the map.