Honestly, these are pretty bold wishes for a free animal in my opinion. Especially given how highly requested they are. They'd make pretty attractive DLC animals. The Scarlet Ibis and the Grey Crowned Crane (especially that) would even be on my small bird wishlist, it just wouldn't make any sense from a business perspective to give highly requested animals away for free.
Plus, yeah, the American Flamingo would just be a recolor. That's the point. It wouldn't be too much effort for zero additional income for a company.
I dont think its that crazy to suggest the Grey Crowned Crane. We have the model and animations for the Red Crowned, the only change is the throat balloon under its neck which I admit might be a deal breaker but we dont know what their plan is.
Frontier rarely puts two birds in one pack, and I fail to see how the Grey Crowned Crane, unless in an avian expansion which is highly unlikely, will be the star of a pack when we have another african bird which is around the same size and is way way more popular, the secretary bird. I think it would be smart for them to get this one out of the way, it gives people another bird which then wouldnt get them mad if we didnt get one in the winter pack assuming its highlands potentially, and they would be able to shift the spotlight on the Secretary Bird for a potential Scrublands or Savannah pack next year.
Also the Red Deer was like at 27 on the meta wishlist, the Crane is only 10 spots ahead of that, there isnt any rule against them choosing a more popular animal as long as it is generally easy for them to make.