It'll get better. Right now I think Tesla drivers have the best options, though perhaps in time the manufacturers of other EVs will also set up good charging networks. VW is likely to be in a good position to do that. I think that if necessary one could take a slow charger and run that off the local mains supply, though that is a pretty poor option. It seems likely that there will be an increase in the number of moderate to fast chargers - for example in hotel car parks and maybe even camp sites.
If I were going anywhere remote I'd want to know that there was adequate backup. We have in the past had problems even with petrol. In one case we took a tortuous route over and around mountains, and ended up with hardly any petrol in a small village in Spain. No garage - but after asking around we found the lady who ran a local bar kept a supply. At least with electricity one could hopefully eventually get sufficient charge to move on in most places - though it could take a long while maybe even 24 hours for a full charge.
I wouldnn't contemplate doing a journey like that in a Nissan Leaf. Renault Zoes are quite good as little runabouts and I've met people who have travelled relatively long distances in those. Inverness to Applecross and back is just about possible without having to charge up again, but it's very tough. At least if things go wrong in the UK hopefully there will be people who can help - though there can be silly problems. One pair I met in a Zoe had to spend an extra night in one place - not because the charging was slow - but because the cable at one public charger would not release from their car, and nobody was able to help them until the following day. Total bummer!

