Why cut echoes? I thought they didn't take up too much development time?
I already mentionned it last night, but it's essentially people believing they take the spot of unique characters, which is far from the truth.
But might as well delve deeper on the subject since just saying words without backing them up doesn't bring a lot to speculation.
For a good comparison, Melee didn't have the time to add a 21st unique character, but it had the time to do 6 clones (
) for a fuller roster.
By that logic, someone might think that 7 clones could mean one unique character, since it'd take more time to make 7 clones than it would to make 6. That's a good logic, but Melee's clones had considerably more effort put into them to make them stand out than Ultimate did for their own Echoes, with none of them feeling like a complete copy of the character they're a clone of.
In fact,
none of these Melee clones are considered Echo Fighters in Ultimate, even the ones that barely got any changes in moveset compared to how they were in Melee such as Pichu or Young Link.
Out of the seven Echoes we have in Ultimate that
are classified as Echoes, only two of them match the amount of effort Melee did, being Lucina and Chrom, and there's a third one who is an Echo Fighter in name only for legacy reasons due to being the first "Echo Fighter" ever in any fighting game, being Ken.
And out of these three, Lucina is returning from Smash 4, meaning most the effort spent on her wasn't even done on Ultimate's development, so she'd have no effect on how much time Echo Fighters took for Ultimate. Dark Pit is a similar case of being a returning clone rather than a new one for Ultimate, except for the fact that he's a carbon copy of copy for all but two moves... which still have the same aminations.
So with all of that said, I don't think there's any realistic scenario where removing all the Echoes from Ultimate would've led to even a single unique character replacing them. With how identical some of them are to their originals, they likely barely took any time compared to a full-fledged unique newcomer.