Rails & Crakes are by nature secretive & skulking birds making photography difficult. The related Coot & Moorhen are by comparison everyday birds that rarely receive the attention they deserve.The rails also have more distant far more impressive relatives that were once part of our avifauna.

Bustards probably only ever had a slim foothold in Scotland with old records from the borders suggesting that grasslands surrounding the Tweed floodplain were once to their liking. The Great Bustard is being re-introduced in England(Salisbury Plain) but suitable habitat probably no longer exists in Scotland & there are no plans for re-introduction here.
The Eurasian Crane is however a different matter. Cranes have successfully colonised East Anglia naturally & there are plans for re-introduction elsewhere in the UK. In Scotland 'pairs' have summered in recent years whilst casual records are increasingly common.
Perhaps Cranes may even dance over Insh marshes in my lifetime!