Yes good points but I always kept a UK bank account. And even at my advanced age I can get a ‘life mortgage’ from LV. I may not need it because downsizing is an aim rather than a shame! We bought a tiny flat a couple of years ago in UK and got back on the electoral role - again your thoughts are right.
I know two English couples who moved back to UK last year from our village, they'd had their houses here over 10 years but then were getting older and so decided to move back to the UK. One couple I haven't heard from since, though I do still appreciate all the toys they gave us from their grandchildren on their departure and hope to see them swing by in the camper van one year in the future as they promised.
Are you planning on buying or renting back in the UK? Assume you won't need a mortgage? If you do...then I suggest first thing you do is try to get a UK bank account if you don't already have one, then get on the electoral register. This is really important for boosting your credit rating. Most companies check with Experian for credit worthiness. Even when letting they will do a credit reference check on you. So if you haven't already done this...start the process. Best of Luck x