It makes total sense to lift pax capacity from 25 to 35mpa on single runway. It's in accordance with Government White paper and provides SE with much needed extra capacity.
Stansted may be in "the wrong place" to some but the 23-24 million pax who pass through it each year may say otherwise. In present times Stansted and many other airports will experience traffic decline but the lifting of this cap gives the airport operator, whether it be BAA or someone else, the opportunity to now focus on getting more business to the airport in future.