It's an interesting and different composition. Most people will prefer an angle with the birds coming toward you, but birds do fly away and I don't think that is necessarily a bad thing for an image, especially with a group. You have good wing positions, but it's a bit crowded for my taste on the sides and bottom. I don't know the capabilities of your software but it would be easy in Photoshop to add canvas and fill it with the sky. An alternative with the group of birds so tight in the frame would have been to go horizontal and not include the top bird.
Some people will not like the tight overlap of the three birds but it doesn't bother me. The closest one is well-defined by the light so it is easy to see.
I prefer the second one -- the square, with the same wish for added canvas on all sides. But other people may have different opinions. What is important is which one you like!
Bella foto! Well, that's my Italian done. I love the light in the image just caressing the underside of the ibis bellies. As said by others, I prefer the re-post, and yes maybe with a bit more room all around. I do like the diagonal flight path. I wouldn't think that adding canvas is "invasive". It's a personal choice. You have a lovely image and adding canvas would just make it that much better.