Personally, when I bake things in modern ovens, I don't use the thermometer either. Sort of, because they still have a thermostat of course. But in general you really don't need a thermometer for baking.
For example, I've baked a pizza enough times _with_ a timer and specific, but different temperatures set that now I need neither and can just adjust the temperature to what I'm used to and know that the pizza only needs a certain amount of time. The end result should be a certain way. As long as it gets there correctly then whether there's a timer/no timer it should be fine.
In general, you can put in things with a large surface-to-volume ratio at almost any point, like pizza, pretzels, or buns. If you put them in early they just get done faster. With larger things like bulky bread loaves, I would wait a bit until the oven cools down somewhat because they are at risk of heating up slowly on the inside while the outside is already done. Personally, I find the bread variants with larger surfaces more appealing, so I don't have a lot of experience with the bulky ones. With pastries it depends on the temperature tolerances of their components.
Really, I would suggest you try it out yourself. I found that intuition works pretty well, even for me as a city-dweller with a non-agricultural background.