The WordPress software comes with several default designs, and for the past few years they’ve been called ‘Twenty Ten’, ‘Twenty Eleven’ etc etc according to when they were introduced.
After some design choices that aren’t suitable for any YES site (and most others!) the latest, imaginatively called ‘Twenty Seventeen’, can work well.
For two examples, see DeepTissueSensual.co.uk’s site for ‘massage with a happy ending in Belfast, Dublin, Glasgow, Aberdeen, Inverness, York, Chester, Preston, Euston and many other areas in the UK and Ireland’ and MatureIndian.co.uk’s site for very naughty times in London, Hertfordshire, and Bedfordshire.
In both cases, there was a picture that worked as the featured image on the front page and not too complicated a menu for other pages. Speaking of which, one of the disadvantages is the way that new pages are not added to the menu in their correct order – they’re always added at the end, so you need to move them manually if that’s not what you want. As the new default theme, it may also become overused by other people.
But at the moment, it’s a quick and easy (and therefore cheap) way of having a good looking site that adapts very well to different screen sizes.