The history
The main issue with Dark Forest is that both its rides were built for the sake of something to advertise. Ug land was built by the original Tussads as a way to re use a few attractions, such as boneshaker to revitalise the area, but they took the opportunity to create a properly themed area with a strong story. Then Tussads was brought by venture capitalists, and Rita was added as a quick way to add a coaster to get guests, a launch coaster could be marketed cheaply, and Ug land was probably the only space they could shoehorn it in. It was given a token theme, but in reality was nothing more than trying to get "new for 2005" attraction. Th13teen sufferred from the fact that it was Merlin's first big investment in the park, and as such, was a rather tentative measure. The budget would have been rather tight, and after the black hole of new ride development swallowed most of the cash, all that is left is well, this. 2 rides that were put there because there was space, with little money to do anything more than give a token gesture to the surrounding area.
The problem
Th13teen works quite well for what it is with its dive into the forest, it feels quite mysterious, and the relative invisibility of it from the queue helps that. Rita is poor. It has an obscene queue due to poor capacity, which coupled with the fact that the ride is just a bit dissapointing after the first hill, often rather uncomfortable, and can barely hold a candle to other Intamin launch coasters, especially if you have ridden stealth is a problem. The incredibly expensive, complicated, and quite frankly huge launch system is just another nail in the coffin. The launch could be so much better, and costs far too much for what it is.
A solution
The idea is an uplifiting area, inspired by british folklore, and centres around Faeries and spirits of the forest, a whimsical, magical idea of a forest hidden just out of sight.
Rip out Rita, pull out the station, and look at your new big open plot of land. Pull the facades off of the games and food units, but keep the actual units, they work fine, and are well balanced for the area. Take Th13teen and pull down that scaffolding. Take out the wraiths and that flipping tesla coil, and start running string lights through the queue, take advantage of no longer needing Rita's queueline to have a new exit that doesn't fell like trailing through an empty queline, and take out the old Th13teen shop containers.
A new play area can go there, to link the ride entrance to the new forest adventure theme. Give Th13teen a new name, and theme the station to a forest adventure, potentially a flight with the Fae or suchsimilar. Take advantage of that helix after the first drop for a headchopper grand tree type theming element, with several smaller trees acting as other obstacles and headchoppers around the course, made of fibreglass to seem suitably etheral, with decorations such as vines, fairy lights, and hints of faces. The drop can now be a prank played by the Fae on you, and the subsequent backwards tunnel could be laced with chasing lights as fairy trails.
In the newly opened up a plaza, a grander focus tree should be built to act as a weenie, taking advantage of the fact that they could probably get away with a taller structure if it matches existing tree cover. This can have an area shop, and some food options around the base. The roots can also form into wood effect paving to lead into differrent rides and attractions.
The site of Rita's launch building is now a cottage in the woods. A queue begins by the current lockers and circles around a garden covering the area of twirling toadstool, before coming back towards the cottage winding its way up a new bank along the lower half of where the old launch building was. Entering the cottage we find a multi launch coaster in that revolves around a journey with Will'o'wisps that launches over teh bottom path, forming an entrance at the bottom, and veers right towards the break in the trees, disapearing behind Th13teen, making use of scream tunnels to add excitement and multimedia opportunities, leading to a showbuilding, that also offers access to maintenance facilities, a la Drayton Manors new intamin. A second launch can bring us back around the focal tree in the Th13teen helix that re-uses the theming, possibly contains supports, and provides some interactivity. The ride can then meander back towards the cottage to disembark.
This is supported by several flat rides, including a Breakdance for a thrill market, a chairswing very much in the style of twirling toadstool, and small young family attraction, perhaps Zamperla demolition derby themed to beetles and/or a beetle race. Lots of benches, and new set pieces to draw the guests down the area, Trees, glowing toadstools etc. wrap it up with some interactive elements, weather that be water play, or light and sound to keep people entertained.
Behold, happy guests, an area unique to the british climate, a lot more positive, and suddenly a new standard for a cohesive area. Guests are drawn in by multiple theming elements towards larger structures, to find a diverse portfolio of themed attractions and supporting shops and food options. Very much like what has been achieved with the new forbidden valley, giving a feel of completeness, and a sense of immersion.
I call first dibs on the front row on the new coaster.
