NST is having issues with its restraints, something ABC need to rectify before they can re-open the attraction. And, budget wise it does make complete sense to close N:ST, and on an experience level it makes sense too.
N:ST was badly received by the GP but also enthusiasts, which did mean the attraction closed a few weeks after opening in 2012 to allow the maze extension & audio changes to be conducted. Now the maze finale is basically done and dusted, they will be looking for ways to improve the attraction as much as possible to ensure it isn't badly received again. Indeed, the press/limelight of the attraction is less intense than it was in 2012, but with the rumoured new coaster being situated in FV, they will need to think of ways to ensure capacity is high for the ride but also that it is indeed, a good attraction to go through, considering a large handful of guests will be in the valley over the next few years. As well as this, with the current issues ST has, there is no way it'll be able to cope with the large influx of guests wishing to visit Galactica & Rollercoaster Restaurant, meaning it does make sense to close the attraction on capacity grounds, as most of the restraints as I said above, are not functional because of a mechanical problem on ABC's behalf. You can argue that not many people will visit for Galactica & RR, but it's generally being marketed as a new rollercoaster and a new experience, therefore you need to ensure the rides can cope in the area. Probably one of the many reasons they chose to get rid of Ripsaw now rather than later.
Budget wise they can save money on rides like N:ST being closed. N:ST is not a popular attraction, even though it opened 4 years ago. It balances between 0-15 minute queues most of the season, and the peak queue-time usually is around the summer months. The GP really will not be asking questions on why N:ST is closed, whereas rides like The Smiler the public are all over. For example, if they chose to close Oblivion over Hex, N:ST, Driving School & Charlie, then the GP would ask questions on why the ride is closed, whereas closing low-profile rides means that the GP will not really notice it on a large scale. Also bare in mind, if Towers are stating that they are conducting 'care-work' on the rides, rides such as Oblivion are much more visible therefore the public would know if TLC is actually happening, or if this is just a cover-up, and will probably link it back to The Smiler crash and put 2+2 together, to make 5 and think that the ride is closed because it is 'un-safe' (that is obviously un-true, but you know what the GP are like sometimes). Whereas closing rides which are primarily indoor attractions, they can get away with saying work is being conducted when it isn't. Chances are, work on the rides won't actually start until later this year, it just allows them to save a bit more money in a time of financial decline. I really do not care that N:ST is closed, it isn't a major attraction to some people and isn't popular with the public. Hex, is obviously a ride which many enthusiasts enjoy, but again the queue for Hex is rarely mind-blowing and therefore the GP won't care, nor for Charlie either.
Bare in mind they will be looking to attract the thrill-seeker/older family style market with Galatica, so closing rides which aren't really regarded as 'thrill' rides means that they aren't doing too much damage. Plus, families already have CBeebies Land, Mutiny, Katanga, Duel, and some rides in CCL as well, will they really care about Charlie & Driving School? I mean, the thrill market/older families didn't seem to care about N:ST in 2015. I forget it is even there most the time.
It makes perfect sense to me why some of the rides are being closed. They were looking to save money, the choice of the rides they are closing makes sense considering all the factors.
