Maybe. You are on the right track, but every bus stop is time robbed from people who are not getting on/off at that stop. Stopping at the entry to every cul-de-sac is too much. So really your 200 meters is 400 meters - the bus should only stop every 400 meters. (the 400 meter is a simple number of discussion, but any book covering this will have several chapters covering all the different trade offs, exceptions and the like: go read the book before arguing the number)

I don't know why a yard would require a cul-de-sac.

Linear density is what matters. Large yards that are deep but narrow are just fine if you want a large yard. Transit needs to pick up/drop off within a reasonable distance of the door without unduly delaying other passengers. A wide yard is a much larger problem, a narrow yard that just has with width of a bedroom and stairs+hall allows for plenty of density for great transit.

A hospital, 10 floor apartment complex, or big shopping malls are places high density, but if they are a long distance down a dead end (cul-de-sac) they are harder for transit to serve than straight street in a suburb despite the much lower density in the suburb.

This is important to remember. People asking for density for the sake of density too often end up with something that doesn't help the cause they want. People who understand what they really want can fight for that, while allowing for less ideal things that are still close enough.

I don't need a large yard, but there are a lot of nice things about having a large yard that I want. Ideally I want my front door to be on Times Square New York City, with a side door to a Caribbean sea beach, a backdoor to livestock pasture, and the other side a mountain - this is of course impossible, but if you don't recognize why each of the above would be desirable you need to learn more about the world. Since it is impossible I have to compromise, but the less I compromise the better.