I used to live in the Surrey stockbroker belt and can think of a few lightly-used stations not many would miss. Boxhill & Westhumble is one, not even walkers use it much, it was mostly a request stop (even trains which were supposed to stop would often just sweep through), some services were not allotted a stop there, and generally it was very little used. The stations between Dorking and Horsham could go too. On the New Guildford Lines, Bookham is miles from the village it is supposed to serve and has little car parking, so consequently saw little use. Effingham Junction is a bleak, windswept place but it has a huge car park and the convenience of services to/from both the Leatherhead and Claygate lines, and I know a lot of Bookhamites would go there in preference to Bookham. Horsley is well used thanks to a good location, even if car parking is tight (again, Effingham offers a decent alternative if you want easier parking). Clandon never seemed to see much use even at peak times, for those going into Guildford it's quicker to just drive and for those commuting up to London from Guildford, they wouldn't even be on that line to start with! London Road Guildford desperately needed investment in passenger facilities, it was well used at peak times by students but there were no indoor waiting rooms, the buildings were mostly boarded up, and it could be a viciously inhospitable place to wait for a train on a cold winter evening.
Down here in Devon, I would certainly close all the stations between Crediton and Barnstaple, and Okehampton is the only station on that line worth keeping open. If I was in a less charitable mood, I'd point out that both LSWR routes have been massive money pits over the last few years and that the investment is unlikely ever to be recouped. Okehampton Station is inconveniently sited miles from the town, and the circuitous route the line takes via Crediton makes it a very slow way of getting to Exeter - by the time you've driven from the town centre or the new housing developments going up on the north side, you can save half an hour by just staying in your car and driving to Exeter. It would have been better left and developed as a preserved railway. The OkeRail campaign seemed to be primarily motivated by nostalgia anyway, as evidenced by their campaign vehicle (often seen parked around town festooned with signage) being a Riley RM...
As for the Alton line in Hampshire, I've heard that, in the 1980s, BR offered it to the MHR, giving them the opportunity to take over the route as far as Farnham. The preservationists turned it down as their finances were not then in great shape (they'd already taken out a big bank loan to finance the Alton extension). Now, the MHR is debt-free, AFAIK, and Farnham would make an attractive destination for them, but maintenance and operational considerations would still apply. I'd be surprised if Alton generated so little traffic that NR/SWR want rid of the line, but Bentley was generally pretty quiet...