Hard one: I have a lot of gripes about Merlin when you compare them to other European parks! AND the you have memories of The parks in the Tussards day.... oh I could list.... but that's not the point of this topic! Also its personal taste!
2BH Merlin excel best at there smaller attraction types - the Dungeons, Madam Tussores, legolands etc. Although I loved the original Dungeons - I'm proud of what Merlin have done to the brand - and expanding it internationally! And appreciate how they overlap their franchises in clever ways! (sealifes in their Theme parks etc).
I thought Heide was a decent park, - you can never tell if that's because of what was already set up before Merlin etc. But the Halloween decor and atmosphere was fab!
Also Th13teen is one of my favourite UK coasters - and Wicker man looks RIGHT up my street and am genuinely excited about riding it! ......Oh and HEX - all is forgiven!