Wi fi/ internet upgrade

[Simon47]

Sorry, missed the update on this ...

Next question: Parts of the new 41m and 40m cables are going to be outdoors, so PE cable is needed for that. I have next to no PVC Cat5E cable left, and will have to buy a new 305m reel of PE, so is there any reason why the whole of the orange cabling shouldn't be in PE? E2Go has unbranded Cat5E PE at £82 + VAT for 305m and Cat6 PE at £114 + VAT. Is there any advantage in using Cat6 over Cat5E for ny application?

At 40m, probably little if any benefit. Cat6 does have slightly thicker cores IIRC, so better for volt drop on a long run using PoE. It's also more expensive, thicker, and harder to terminate.

Plugsandsparks suggests Ubiquiti UAP-AC Pro access points, and while I've no doubt that these are excellent devices, I suspect that they deliver much more than I need, and at a price that reflects this. I see that Ubiquiti also list the Unifi AP-AC Lite at a much affordable £68 + VAT, but unfortunately they don't appear to be in stock anywhere.
Can anyone explain, in layman's terms, what the difference is between these, and perhaps suggest a lower priced POE ceiling mounted access point. I've found the TP-Link Omada EAP110 that, apart from appearing to be an odd looking object, I assume does the job at £33 + VAT.

The AC-Lite uses passive PoE @ 24V - meaning you either need to use the supplied power injector, or a switch with the ability to supply it (again, at a cost, Ubiqiti do switches with that ability). Part of the reason is that in some countries, 48V wiring for 802.11af PoE has to be done by a licensed electrician while 24V can be DIY - in some ways, it's a pity the active PoE spec didn't allow for that, but it would have added significant complexity.
Software and ability wise I don't think there's any difference between the Pro and Lite versions - and as you say, most likely overkill for most homes. I need to upgrade some of my other kit to support it, but one good use is running multiple SSIDs (wireless networks) on separate VLANs (virtual LANs, effectively segregating traffic without having to duplicate all your switches and wiring) to keep the untrustworthy IoT carp away from stuff you care about. The Ubiquiti stuff supports 4 SSIDs, others support more - IIRC I once installed some Draytek kit that could support 16 SSIDs !
I don't know the specific unit you've mentioned, but TP-Link are known as a manufacturer of decent low-end kit that's fairly reliable but generally not massively capable in terms of features provided. I'd certainly pick TP-Link over many other brands.

No one has commented on the 8m overhead suspended section of cable. My own feeling is that the construction of Cat5E PE is fairly similar to the 3 pair PE cable used by Openreach/BT for old copper connections, and they are suspended for spans of many times my 8m, so should be OK.

Actually, the construction is very different. OR dropwire has strength fibres (aramid ?) to take the tension, so the copper pairs shouldn't be carrying much, if any, load. I don't think I'd want to have an 8m span of standard network cable self-supported - so as suggested, fasten it to a support wire. Also, provide good flexing loops at each end - it'll flap about i the wind, and if you make the movement be taken up in a short bit of cable it will eventually break the solid cores.