One of my favourite ships in the series easily, its a bit out of left field but it just resonates with me. I wanted to make this not only because I love Trouble and flutters but I also wanted to illustrate how I Head-canon the sizes of ponies to be compared to horses.
 
I scale Trouble to be 18Hands High at the withers which is average for Shire horses and fluttershy to be 12Hands High, who I imagine to be tall for a mare of her species. Ive always pictured the average ponies we see in the show to range from 11-13HH with Luna as we see her at the end of the show being 14HH and Celestia and Chrysalis being 15HH.  
I plan to do a full size comparison chart in the near future as well as solidify my Head-canons for all characters and species in the show.  
I should probably note that Trouble is meant to be a clydesdale but I felt it somewhat amusing to make him a Shire since his last name is clyde and also I have a huge affinity for Shires as I own one who goes by the name of StanleyLove.  
In my universe interbreeding betwen ponies and shires/clydesdales/zebras/draconequss ect ect is a relitivley new and socially acceptable thing. Breeds like the shire were misunderstood and often stood as ‘myths’ within traditional culture (the pony equivalent of BigFoot, or more aptly BigHoof).  
I didnt give Trouble his Cutie mark as I imagine him to be a pure Shire with no ‘Pony’ in his lineage :)