Postcard Feedback for Min
In General
Consider a different font: this one is clean and readable, but fairly plain.
Make sure the punctuation is correct; there's a lot of missing periods.
Jon Snow
Desktop size: consider a larger font; there's a lot of empty space above the heads of the crowd that could be used.
Mobile size: try center-justifying the quote. Jon is so centered in the picture, so centering the text would help the flow of the image.
Edward Stark
Desktop size: try a larger font again. The picture is also fairly low quality, try to find a different one.
Mobile size: this is a great place to fit the text around the image. It's a short quote, but consider offsetting the attribution from the actual quote to fit around his head.
Crop out the HBO logo; it only distracts from the quote.
Tyrion Lannister
Desktop size: larger font again. Try off-centering the image by moving Tyrion to the right; there's a lot of empty space on the right half that could be used.
Mobile size: try center-justifying the quote, for the same reason as Jon.