It's interesting... I really would love to see a major new dark ride. It's something which Towers has been needing for a good while now, especially given the thrill lineup has recently expanded again with The Smiler. When you consider that a park as small PL still had until this year 4 (Albeit pretty naff) large scale transit dark rides, whilst Alton has just Duel and, ughh, Charlie.
Has any more been heard about Ghost at Legoland Billund? As far as I'm aware it's to be the first really attempt by Merlin at a major dark ride with a transit system included. It could give us a good indication of wether or not they can pull it off.
Personally I think that Merlin could do it rather well. I mean, when they tend to produce major theming elements they usually come out half decent. It just tends to be what's around them and the support which lets them down (The Marmaliser in a dirty concrete pit, or aside from the Crypt Th13teen having bugger all outside for example). In a dark ride you have a different level of freedom. If you don't want people to see something it can be much easier to hide, be it by careful lighting, or minor obstructions.
Take the original Haunted House; the two demons in the dining room and the room of a thousand bluuuuueghs all worked pretty well, and on the whole appear to have been pretty effective. However, the workings of these props are all actually sat just feet away from the riders, and it's only thanks to the poor hash of Duel that they've become exposed. I guess what I'm trying to say is it's easier to cover up things in the dark whilst retaining an immersive experience.
To pick on the only Merlin dark ride at Towers, I wouldn't particularly say the theming on Sub-Terra is
bad. When I did it I thought that the main chamber was pretty well done actually. It was the actual execution of the ride itself which let it down, with poor show execution and completely failing to achieve the project brief (This was on opening day of V.1!).
I don't know. We haven't really seen enough of them to be able to fully write off a major Merlin dark ride if you ask me, but I do have a slight feeling that it could be something they might do well.
As for location, well if it's going on Coaster Corner I'd expect (Read: Hope) that it may mean something gets done to Charlie at long last. Particularly if they planned on having a brand new multi-million pound dark ride aimed at the same target market sat next door it probably won't be looking too great in comparison!
For me, I've always fancied the idea of a dark ride built on the coach carpark for the Katanga area. I was discussing it with
@Sammy the other day. If you can imagine where the path from Mutiny Bay turns right to the bridge over the rapids (Just past the waterfalls), create a T junction there, with a new path going left through the trees into a small (Like half the size of Gloomy Wood minus Waffles and Ices) jungle themed area, with some form of ruins or temple in front of the guests, screening the car park from view, and creating a small isolated plaza.
Within lies an Intamin Tow Boat ride system (Fata Morgana), which is just a gentle boat ride through some vast enclosed temple and jungle scenes, maybe with a basic voyage to a lost tribe story line (Maybe climbing to a finale of discovering the hostile tribe and having to flee for your lives back out of the temple). It'd be a simple idea, but could be pulled off incredibly well and breath new life into Katanga without ruining what's already there (I'm strongly against adding any rides directly into the main island area. The area was built for those two rides along. Anything new simply must be set aside from them and isolated).
Just my thoughts, although I do agree with some others that Merlin's concept of cycling budgets by year seems to have become more lax recently, so I wouldn't expect anything too major until perhaps 2017 now. Probably a new thrill flat next year to replace Subs, and maybe some smaller filler attraction to go in CBeebies if needed, then again another new flat to replace something old the year after. We can certainly live without a new Secret Weapon for a few years now though if you ask me. Provided it doesn't collapse The Smiler should tide them over for a few years, hopefully allowing for a fully formulated concept and execution next time around