Here in Wales i think a coach firm called Kingfisher Travel do over night stays in France, i'm not sure if they have feeder connections to other parts of the Uk though , i have always travelled with Ferris and prefer the straight through journey , because your outside your hotel early morning , the overnight stop adds almost another day of travelling , but we all have our own preferences, for whatever reasons .

http://www.kingfishertravel.com

i believe shearings/wallace arnold do overnight stops,as i believe does leger holidays but i'm not sure on that one, but the additional cost makes it very expensive.
the standard of coaches now is very high, especially ferris platinum and siesta, and although i dont tend to sleep much on them i find that i can catnap through the night and am not completely shattered on arrival in resort.
i have found over my trips that if you pack swimming gear and towel in hand luggage, by the time you get checked in,have breakfast -i always wait till i get to my resort and have a full breakfast in a cafe near my hotel- if you do not get immediate access to your room because of cleaning work still going on,, at least you can get changed and have a little doze by the pool.
in any event i do like the spanish idea of a siesta and tend to indulge in that, so am always ready for going out on the first night .
hope this helps.