Yes, I completely agree that Lucina is every bit as similar to Marth as Chrom is to Ike.
...
And while we're on the topic, let's talk about how people consistently state that Lucina is 'combatively redundant', i.e. her fighting style is redundant, when through two cutscenes and various supports and in-game assertions Lucina is both shown and stated to have a mirrored, nearly identical fighting style to a completely different swordsman. Chrom. Her father, the man who taught her to fight. The 'likeliest', 'not-like-Marth-but-totally-an-Ike-clone" character.
Seriously, detractors can't even keep their flawed logic consistent.