Not a networking expert at all, but I posed the same question you're asking when I was setting up networking in my house... The consensus was mixed. So I did what was easiest which was to exactly what you did. I doo believe that one single switch would be best, but i have not really noticed any performance hits doing it my way and your way..
AM I THE ONLY OASIS IN THE DESERT OF STUPIDITY......" SIR BRICKENBOCKER"
It really come so down to how you use your network. To answer your first question it is better to use one big switch then many smaller switches. This is from if you fully load your network you get full speed instead of having some decrease in speed at transition points. For most home users you will probably never see this going with a multiple switch solution. It is not bad to run from one switch to another, but do not chain too many together two or three should be your limits for good speed. The other thing is to try to connect devices that talk a lot together to the same switch so that it does not have to propagate through your network and it will improve communication times. Using one switch can help network problem shooting if you ever need to do it.
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