I disagree while a replacement Bus/Coach might be regarded a less good option if the economics justified it then perhaps it should happen. For the Bentham route I would envisage a replacement bus between Settle and Lancaster, which could serve Clapham village rather than the miles away station and also a few villages on the route not currently served by the rail service.
Longer distance passengers from West Yorkshire would use the Copy Pit route (which at the time the S&C was posted for closure the reinstated service was still in its infancy) instead with possibly a couple of current Blackpool service being routed to Morecambe instead of Blackpool.
Also I have never really advocated closing both the S&C and the Bentham route, a case of one or the other, and I suspect the economics of the S&C are much better but then again we really need to see some figures on a line by line basis rather than guessing.
There's not really any justification for closing the Bentham route. It's more or less run in conjunction with the Settle Carlisle and doesn't have any signalling or staffing of it's own to speak of. It's about as frugal a route as you can expect to find, yet finds itself of good use to the North.
I dispute the idea that a bus connection would be an adequate replacement, particularly for those travelling further afield. Long bus plus longish train journey isn't going to be as acceptable to local residents as even a longish train journey.
Also, as a regular traveler on both the Bentham and Settle - Carlisle routes, I note that there are a fair number of people who travel from Shipley, Bingley and Skipton to the North and West. Forcing them to double back via Copy Pit isn't going to be an acceptable alternative. This plus the fact that the Bentham and Copy Pit lines complement eachother when one or the other are closed (This was particularly noticable during the closure of Holme tunnel).
If bus/coach is a less good option, then it must be resisted, full stop. Even a lesser used line such as Bentham roughly follows the routes of the A66, A683 and A687. We wouldn't close these willy nilly, so there's no excuse for closing the railway service. And just because you made a lifestyle choice to live in a town without a railway station, doesn't have any effect on those of us who depend on the railway for day to day travel.
If it was my choice, I'd like to see the service amended in the morning to make it more useful to locals commuting into Leeds and Lancaster from the hinterland.
I agree Whitby is a more difficult one, and in some ways its a double edged sword, as you say it was retained for the reasons you mentioned but if you were going to maintain a service to Whitby it doesn't strike as been the best route to maintain a service to Whitby.
I'm sorry, but the fact that there was once another route (which somebody closed in error, lest we forget), has absolutely no bearing on the value of the existing route today. There are many people who use the line to travel from Middlesborough and further North for whom the route is ideal, this on top of the purpose for which it was saved.