I would take a credit and a debit card and also plan to get some cash, even just £50-100 worth (either order to collect in the UK, or plan to get it on arrival) so I have it for transport or food/drink on the first day.
To not have any cash seems reckless as in many countries, some places won't take it, especially for smaller purchases. I'd also make sure none of my cards charged for overseas purchases or cash withdrawals, look on Moneysaving Expert for a full explanation. I find that the people who say they 'never need cash' live a very urban/suburban lifestyle so aren't stuck because a small business or car park in a rural area is cash only. They also don't think about the extra expense that paying by card brings - all that commission, fees and 'convenience charges' add up. They also don't care about the amount of money the retailer loses in card charges.
You can always use your card when accepted and then spend the cash anyway if it's still left at the end of your holiday. Or get some more from a cashpoint if you need it.
I would do this wherever I'm going so it covers all bases unless I know that everywhere takes cards, even for small purchases. I've never been out of Europe, but Iceland was the only country I felt comfortable without any cash at all, otherwise I've found that:
In Germany, many restaurants and cafes are cash only.
In Poland, public toilets are usually chargeable and cash only.
In Spain, many smaller/out of the way shops and bars are cash only or won't take cards for under about 10 euro. Also buses are often cash, special card or app only, you can't pay with a bank card. However, it's hard to find a cash machine that doesn't charge to withdraw cash, so use your euros efficiently by using your card where you can. But as I go to euro countries a few times a year, I just keep any left over until next time.
In Denmark, there was a surcharge for paying by credit card, but a debit card was free.
Plus as you say, if there's a tipping culture, you need cash for that.