Loved Rebus - even when Rankin and most others grew tired of him. I have discovered Stuart MacBride's books - though I feel that his main character Logan is overshadowed by DI Steel. What a gutsy 'wee lassie' she is !! I just love her... I started Elizabeth George's latest, what can I say........she's gone to the bottom of my reading pile.
as much as i'm a fan of macbride (despite the decapitations and whatnot), i'm finding myself exhausted by the end of each book and angry that logan never gets any time off! steel is a cack though. i've only tried one elizabeth george and got bored and never finished it. i'm currently reading leigh redhead's latest 'thrill city' which is loads of fun.
If you're looking for English or Scottish series in particular - Caro Ramsay and Elena Forbes could also be worth having a look at. Neil Cross is you're not looking for a series progression but great standalones.