Focusing on "thrills" is likely why the park went over a decade with only Ghost Train to show for it. There's not as much money in teenage yobos as there is in families. And Thorpe already makes it an intimidating enough place for families to visit as it is. They need some family thrill and whole family rides.
Contrary to popular opinion, I don’t think thrills was Thorpe Park’s issue. Thrills worked for them in the 2000s and early 2010s. It was only Swarm’s “failure” in 2012 and the things that happened after that started to make things go awry. It’s worth remembering that Thorpe Park’s most successful years in terms of attendance were 2009-2011, and the park’s prospects went up and up throughout the 2000s.
My opinion is that Thorpe Park’s later rut was caused by a general lack of meaningful investment post-Swarm, but also the fact that they arguably went primarily for things with overly niche appeal when they did invest post-Swarm. Things like Black Mirror and The Walking Dead didn’t have the widespread appeal of something like a big coaster, and to a degree, I’d even argue that Derren Brown’s Ghost Train had overly niche appeal for a major investment. Say what you will about big coasters, but they can appeal to a broad cross-section of the older park-visiting populace. Did Derren Brown, as a 13+ VR horror dark ride, appeal to nearly as broad of a cross-section? I’m not convinced. Had they gone with a more “traditional” dark ride with more universal appeal, I think it could have done, but I don’t think the ride they went for had nearly wide enough appeal for something that cost as much as it did.
A lot of people seem to think that Thorpe Park needs to go back to the 80s and become a family park again to be successful. I disagree with this. With Legoland, Chessington and Paultons Park nearby, I think the young family market in London and the South East is already saturated, so I don’t think Thorpe Park should go back to heavily targeting young families. I think thrills is their USP within the region, and they should stick with it.
With that being said, I think they should broaden the scope of “thrills” a tad. Now that they’ve got a big hyper in the form of Hyperia, I think they could do with a 1.2m height restriction, preferably non-inverting, “starter” thrill coaster of some form. I think something like a GCI woodie would fit the bill, personally. I also think that a more “traditional”, universally appealing dark ride that isn’t Ghost Train wouldn’t hurt either. They should reverse the Walking Dead retheme and make X a universally appealing attraction with a low height restriction again. That would be an easy win.
So my opinion is that I don’t think Thorpe Park needs to totally reinvent the wheel and start aggressively targeting young families again. I think they should stick with thrills. However, I think it would pay for them to broaden the scope of “thrills” to appeal to older families as well as teens and young adults and build things like a 1.2m thrill coaster and a more universally appealing dark ride.
Confirmation of the empty land being earmarked for development or just another little tease for the fans? 
what if they are linked, the RMC cup and the watch this space are both on cups, this could be a multiple video promo so... they must be building an RMC behind the swarm.