Travel from Glasgow to Edinburgh

Start here: http://www.glasgowairport.com/im-departing/getting-here
Although it says "getting here" it works in reverse. Looks to be 3 options.
1. Bus to Glasgow City Center, then bus to Edinburgh.
2. Bus to Glasgow City Center, then train to Edinburgh.
3. Bus to Paisley Gilmour St station, then train to Glasgow Central, then train to Edinburgh.

You can also take the train into Glasgow from the airport, then another train to Edinburgh.

I think that was option 3.

Option 2 worked best for me . The 500 bus leaves every few minutes from Stance 1 right in front of Glasgow Terminal . Exit the bus at Queen Street Station , and take the commuter train ( also , every few minutes ) to Edinburgh Waverley .

done this trip quite a few times over the years, bus usually works best as the airport bus stops in the next stance to the Edinburgh bus,so no walking around dragging bags and the prices are pretty good. train will be slightly quicker but depending on time of day can be very crowded.

A slightly different question--has anyone ever done the Freedom of Scotland Travelpass? Is it worth it? We are going to take the train from Ebinburgh to Glasgow, say in Glasgow a day, then take the scenic railway to Oban, then eventually take the Ferry to Mull and Iona (and I think all those stops are covered). Any advice?