Hi!
I spend a bit of time in the card game and have friendly enough relations with nations that I gift and receive cards with some regularity. On top of this, I transfer cards between nations with frequency, again as gifts. This occasionally results in lost recognition of goodwill gifts, as I expect the card to have come from a nation I control.
The current system for discovering if a gifted card is from a friend (and who it's from, if I need to thank them), is to click notices, click the card, click trades history, and then search for my nation's name. This isn't much hassle for one or two gifted cards, but when receiving gifts in the middle of a mass transfer It can easily get lost, and tracking down which card came from where becomes quite laborious.
My suggestion is to show the nation's name when you are gifted a card in the notices. I think it would help reinforce the camaraderie seen in several sectors of nationstates, and make gifted cards more fun to give and receive.