Really depends on which era of Gemma you choose though, and of course what the competition chooses.
For example, the UK has the Sam Fender, Coldplay and Harry Styles card over me whenever they feel they want to use it
The US could really do wonders if they hit particular songs from Sufjan Stevens, Paramore. Canada with Avril Lavigne and Australia with Troye.
Good example would be when you've sent Gavin James, he has such amazing music, but thankfully the song you ended up choosing gave at least a fighting chance for other songs in the contest, because it wasn't my top 10 favourite piece of his