Guys, before this gets ugly, it's probably useful to know that FunkMaster had a thread running previously where he described his plans for sources and such. Have a read here:
https://www.diynot.com/diy/threads/move-virgin-wall-box-and-network.484538/
I normally prefer it if an OP contains all the relevant info rather than asking the readers to rely on knowledge of past threads. However, given that the questions related simply to hiding AV cables which is then mostly about wall construction, then I think that the related background info was sufficient to answer the question. The thread has been taken in a different direction by some of the subsequent replies, and it's perfectly understandable why. It probably hasn't helped though that some posts have been edited which makes other replies look a bit odd, and there appears to be a completely unrelated post in here too ... lol.
Anyway, just to keep things on track, FunkMaster's sources are likely to be a Tivo box (SD, HD, Netflix psuedo-4K), Apple TV (4th Gen is max HD 1080p only, 5th Gen may do 4K when launched later in the year - tbc), PS4 (pseudo 4K). Unless there's plans to add an AV Receiver with multiple HDMI in and a single HDMI out to the TV then the sources will wire directly to the 3 or 4 HDMI inputs on the telly. This of course means that the conduit/trunking must be large enough to host a network cable, possibly an optical, and at least two HDMI cables and still leave room for a 3rd HDMI plug to be pulled without snagging on the existing cables. Personally I'd also include an aerial coax, but that's a choice for FunkMaster. The answer then is either one very large trunking, or two or three smaller ones.
Let's try and leave out any rather pointless debates about whether HD comes from only Sky or elsewhere too. We've had HD in the UK long enough for any serious contributor here to know that Terrestrial, and the boxes from Sky, Virgin Media and BT Vision all deliver versions of HD.
As to whether HD will look good or not on a 60-65" TV then the answer is Yes/No/Maybe. There are a lot of factors that can swing the result one way or the other. These include viewing distance; TV quality; picture set-up; source quality - and this includes the quality of the original material and the compression applied for the transport stream, and of course the screen size. There are just too many factors to give a definitive and all encompassing thumbs up/thumbs down.