It looks like a decent enough schedule to me. The only reservation I have is that you are flying into my local airport. Now despite its aspirations to be more ('Leeds Bradford International Airport') it remains a regional and fairly small airport. Worse, the transport links to and from are poor. There are bus links into Leeds Centre, a good ten miles away and taxis and then that's it. No rail links. A half thought through rail link is in the pipeline but nobody is holding their breath on that one. Local councils attitude is build more roads but even they won't go right to the airport and again they are unlikely to be built in the near future.
If it were me I would take a taxi to Guisley or Menston Railway station (aassuming you are not arriving very early or late - unlikely into LBIA) and take the train from either station straight into Leeds railway station (Guiseley is the nearer station to Leeds and both are on the same 'Wharfedale' line) direct to connect with your train to York. We pay about £15 for a taxi home from the airport which is about five miles away and you should be paying something similar to Guiseley/Menston. Price for an off peak single into Leeds by rail will be approx £5.00 per person. Do make sure you have a ticket before boarding these trains. Guiseley is a manned station with ticket office, but Menston isn't I don't think, so you'd need to buy a ticket from the machine, which only accepts credit/ debit cards. If none of your cards will word in the machine you need to ask the machine for a 'Promise to Pay' slip and buy a ticket from the conductor/guard on the train or at the station on arrival. Without ticket or Promise slip they will attempt to fine you £20 per person on top of the fare. They are trying to cut down on ticket dodgers and are currently being quite draconian about it. So forewarned is forearmed!
Other than that you will be flying into the highest airport in the country, but if you approach from the right direction you get a lovely look at the moors below!
Have a great trip! Scotland in my view, rarely disappoints although I would be tempted to try fit in a trip to Glencoe as mountains are more my thing!
Ian