The yard we are at is really nice, low-key, friendly people and a great arena. Last winter we could ride most days as the snow was easy to clear and floodlights are really good. The only downside is that there is limited turnout in the winter (maybe every 2nd day) but I think that is the case...
Try James McCullough, he is an Event rider but is classically trained in dressage and a very good horseman. Based in Claverdon, www.jameseventing.com :)