I've had vivaia come up in my feed before now and wondered too. They look fine to me but I think the odd thing that Hotter and Ecco do are fine too. I think comfort trumps fashion and not all comfortable things are style free. Sore feet feeds into your face and if your feet are happy so will be your smile.
I need a bit of arch support and the shoes you have linked to seem to have it. I'm not wholly persuaded by knitted shoes though.
My mantra has always been that if a shoe is not comfortable in the shop, no amount of breaking it in will make it comfortable, hence I have always avoided Birkenstock and DMs - not that I like them much.
Day to day I value comfort, don't work where there is a strict dress code and people can happily wear trainers, birkies and smartish jeans with a smattering of creative/arty types. I am neither and don't own a pair of trainers.
Where I work, buildings are far apart in a quasi rural location and there are unmade paths between them so smart, heeled shoes are completely out. Everyone tends to wear flats.
Occasionally I wear smart low heeled flats, usually for smart events: weddings, opera, smart formal dinners, parties, etc. My go to's for special occasions are LKB, Stuart Weitzman and for DS's wedding the only colour match I could find was the classic Ferragamo court - and the price was faint worthy.
In winter when I'm in my boots I usually change into a neat flat shoe in the office. Since Christmas a black suede pointy flat with gold at the front from Clarks. There is no way Incoukd wear them if I were standing lots but they are fine at my desk and in the office. My jaw drops every time I see a ticket with £80 plus for a pair of Clarks shoes at present.