Are you going to put in Ethernet wall outlets or just let the cables hang? Since anything you're going to connect to the Ethernet will probably have to be plugged into a regular AC receptacle, then near such a receptacle. If you're going to have a desk, then behind or right next to the desk.

The simple answer is wherever you plan on using devices that will have an Ethernet connection. Some “smart” televisions, some television set top boxes, desktop computers, and some laptop computers. Devices like Alexa and Google Home plus (most) Roku type boxes don’t have an Ethernet port.

It all really comes down to how you plan on positioning things in your home.

Unless the structure itself is very large, has thick walls, or your neighborhood (because of density of signals) impedes Wifi use, I'd think twice about the benefit of running wire.

One of my relatives bought a house that the seller had wired. It wasn't until they moved in and started getting things set up that he discovered how inconveniently located the "home run" site was (terminus where all wires run). He abandoned the thought of using wire and has a very stable and useful Wifi setup in its place, with Google hardware.

I'm currently at my second residence where the homes are closer together than my main home. I checked, there are 18 separate wifi signals currently visible from the PC I'm using now (wirelessly). Funny thing is, my wifi service is excellent everywhere with just one transmission point. and I have 15 devices connected. Never a problem. I choose a channel that has less traffic and check it every few months to see how neighbor signals have been adjusted. If needed, it's easy to move to a less crowded channel.

In places where home size or wall thickness is an issue, the new mesh technology devices can provide great Wifi service over a large area.

One advantage with wired is that you don't need to use a password.

Password entry is a one time thing. I have a variety of devices that are awkward to enter a password for - thermostats, TVs, DVD players, music players. But it doesn't need to be done a second time unless you change the password.

I'm not a proponent of using passwords that look like they came from the NSA or CIA, sequences like 4Y%m!!pp92zq5@@. Mine are nonsense words easy to type and easy to remember. If you're good enough to break my passwords, however unlikely, welcome aboard! There's nothing to find.