I used to make sure I had space for eggs simply because I've been trying to hatch an Alolan Vulpix. After finally getting one last week after who knows how many eggs I try to keep space for two 7k eggs, but don't fret if I end up missing out.
I don't know what's worse, an endless sea of 7k eggs with the small hatch pool they have or getting an endless sea of 5k eggs with a much more massive pool yet somehow only hatching Nosepass and Carvanha.