Just a counter to the "Overengineered" thread, which there are lots of examples to choose from, I imagine.
Corrour
Connon Bridge
Probably the 2 most obvious examples one can give for this one I reckon.
Stoke-on-Trent as the line is too congested for what its currently used for and it needs more platforms.
What's your reasoning for those two stations?
Accidently typed Corrour - I just realised it was Beauly I was thinking of
Beauly and Connon Bridge - the shortest platforms in the UK which aren't long enough to support a full carriage, yet both have combined usage of around 75,000.
Plenty of stations which have the platforms designed for even greater this figure have lower usage. Beauly and Connon Bridge were only designed to cope with 36,000 passengers a year, with the former smashing that with just shy of 60,000.
It could be the time of day that I've travelled up there but I have never seen a train so busy that the short platform ended up causing inconvenience to passengers.I'm surprised that Beauly hasn't had it's platform extended given it's usage.
Could Fenchurch Street in London have done with an extra platform or two?
Farringdon is seriously constrained by its location despite gaining a 50% extension to cope with 12 cars. In 2015/16, it had a total entry/exit count of over 12 million passengers which if current trends continue, could double by 2030. Provided services keep running through the Thameslink core in the peak, the platform can be kept clear enough given the capacity of the class 700s but just as Thameslink Kings Cross station had to abandoned when 12 car trains were introduced, I suspect that something will be done about Farringdon before the class 700s are life expired.
On the tube, i would say that Clapham North and Clapham Common are candidates for upgrading sometime soon. The C&SLR practice of a single narrow island platform within a large tunnel shared with two running tracks has gradualy been engineered out, (I can remember the Angel and Euston Bank branch examples).
Waterbeach. Hitting a point where station useage is constrained by only being able to accommodate 4-car trains that in the morning peak arrive already full from Ely. Plans are for temporary 8-car extension followed by building a whole new, possibly 12-car, station to the north.
I'd add Cambridge. It's lack of passenger circulation area on Platform 1 and 4 is very noticeable on Friday evenings and Saturday mornings.
Chelmsford, will get some relief if Beaulieu is ever built.
Ipswich, very short of 'country' facing platform space.