Anything that can be hard-wired should be. Even if the device has built-in wireless, if it also has an Ethernet socket then that should be connection priority #1 if for no other reason than it lightens the load on the wireless network to help those devices that only have wireless as a connection option. We've been through the plague of overcrowded 2.4GHz. It's only a matter of time before 5GHz starts to show the strain too.
For sharing Virgin/Sky etc in to multiple rooms can be achieved with a simple HDMI splitter. If you're not yet running with these services at 4K UHD resolution then you will be at some point in the future, so it makes sense to plan for that now. This means getting a 4K UHD splitter that is HDCP 2.2 compliant and supports at least HDMI 2.0 These are the standards that allow the good stuff such as Dolby Vision to get from a source (if supported) to a capable display.
Once the splitter is sorted then it's time to think about getting the signal from one room to another. This is where I have to say that HDMI is a bad idea for distance work of this kind. Standard UHD-rated copper HDMI cable has a little trouble It has some trouble with 4K UHD resolution signals once you get past the 8 mtr mark. This means that you're probably going to have to switch to a fibre cable to guarantee getting a signal, and that's where things start to get expensive.
HDMI cables are a bit like a boat anchor. Chucking some HDMI cable in to the walls anchors you to the standard at that time. We've seen though how HDMI standards have shifted fairly significantly in the last 10 years as more and more data in the form of higher resolution and more colours and a bigger dynamic range and more frames per second and more audio channels get touted as the next great thing.
We're also at the point now where 8K TV is starting to become mainstream. Just as was the case with the early days of 4K UHD, there's not much in the way of source material to view, but it's only 5 years since Sky started to broadcast in UHD and 4K UHD Blu-ray discs started hitting the shelves, and now look where we are. You can see how it would be possible that the cable you've installed can be rendered useless -
or at least very limited - because it is anchored to the standards of today.
My recommendation is to look at installing a couple of CAT6 cables in place of where you thought you might have put in HDMI cable. This won't be for networking and Internet access. It's an alternative point-to-point cable to replace HDMI. To make use of this cable when you're ready, you'll buy two boxes called Baluns. The one near the Virgin/Sky STB will convert whatever HDMI standard we're running at that time to a signal that can travel over these twisted pair cables. The box near the far-end TV will convert the signal back. You'll then hook up with a short HDMI cable in to the TV.
Get the right sort of balun and you'll have a solution for remote control relaying too. There are Baluns with an integrated IR system. A receiver at the far TV picks up the Sky/Virgin/other IR handset signals and passes then back down the CAT cable where they're converted back to IR. A lead with an IR emitter is then used to bring the signal close enough to the IR window on the STB that it responds to the controls. There's a very slight delay of a fraction of a second in this relaying process, but in all other respects it works seamlessly.
The advantage of Baluns is that the boxes can be changed and upgraded as new video standard become mainstream.
Where you're getting trades in to do the refurb' work then it's good contingency planning to install '+1' spare cable. What this means is if your balun or network connection on to the room requires two cable, then have the spark run 2'+1' (3) so that if a joiner / plumber / spark or other trade manages to put a nail through on then you have a backup.
As for the network wiring, I would put two+1 cables behind any TV. Much as I hate to admit it being a physical media fan, the future of video is streaming. I would be incredibly surprised if we see another physical disc format after 4K UHD Blu-ray. In it's defence I will say the a 4K UHD BD disc massacres streaming for picture and sound quality, but the average viewer/consumer either doesn't know or doesn't care. Access to content overrides any quality concerns. Most of my viewing is streamed too, so I can appreciate the case for convenience.
@SpecialK's suggestion of having wiring in place for wireless access points is very wise. Trying to cover a whole house with Wi-Fi from a single wireless router that might not be in the best place, or might not even be that good, or possibly just isn't set up right is always going to be a challenge. Even when things are optimised there's always going to be some dead spots or occasions when more devices are being used at the same time than the ordinary wireless network can comfortably cope with. That's when wireless access points with hardwiring back to the main switch start to pay off.
