As a new member I am going to share my thoughts on these two great rides.
Thirteen - great name, great feature, decent first drop but too short
Wicker Man - another great name, great layout for the space, another amazing first drop, a few pops of airtime and great theming (Although none of the effects all work at once).
I have always had a special feeling towards thirteen; I rode it before I knew anything about Alton Towers as soon as I was old enough. My dad didn't tell me what happened and it freaked me out but I loved it.
Wicker Man also has a special place as I have had some great rides on it.
The both have one drawback in common. They are both family coasters themed too well. In this I mean that the kids get scared really easily. I have actually seen kids cry and scream during wicker mans pre show. Which doesn't put them in the mood to enjoy the ride. I myself remember the music for thirteen with the countdown and the girl breathing incredibly scary. I actually had a nightmare that night.
About thirteens marketing, I think I take a similar view to John Wardley that it was needed to get people back and it worked. It needed to show there were new bosses in town who wanted to make 'Alton towers great again' It wasn't ideal however the needed something to put them in the game and the general public think of Alton Towers as having the most scary rollercoasters in the world with some great rides for the kids; this reputation has been built up over the years and is unshakeable from the public mind. When they build new rides they have to fur fill this criteria otherwise people don't come.
So I think wicker man edges it for being the better ride but thirteen has a special place in my heart and Alton towers history being the first project merlin did at Alton. The first in which they got John Wardley back in (And not just as a PR stunt man like with rita). Of course wicker man also has historical significance in putting Alton Towers back in the game after the smiler crash which threw them completely off. Sorry about the long winded answer I just thought I'd share my rather complex thoughts about both of these rides.