I'm 99 % chill. because I personally decided to not invest so much into who is more likely to get shown off (lets be real, the definition of "Big 3 E3 character" is so broad it could be practically anyone notable). Only a bit nervous since I've invested a bit emotionally ("What if a character I really like gets in"?), but not that much.
I'm of two minds when it comes to that. On one hand, I'm honestly fine with how Chrom is currently because he plays differently from Roy. Not just because of lack of sweet / sourspot, but also since the two approach situations differently. Roy wants to bearhug his opponent and consistently pressure: a Roy that gets going can feel like a ****ing unstoppable pain train. Chrom aims to strike a balance between aggression and patience - the character prefers this not only because he lacks the sourspot, but also since he does not want to be off stage. At all. Chrom has more flexibility on stage, but Roy can usually survive a bit longer since his Up B has a little horizontal movement.
On the other hand, Luna would've made for a more interesting kit, and given that 3 characters are derived from Marth moving them away from Marth would've been much more engaging to experiment with. Any such changes would be precarious becauce of what I said above - Roy / Chrom is already an interesting contrast. It's certainly possible, but would need finetuning.
Then again, I'm not in favor of Chrom being an Ike echo because Ike's moveset doesn't fully evoke that balance between aggression and patience. Ike wants to wall people out and get the room for follow ups / additional hard hitting attacks - which would be more difficult base to build Chrom from. Of course, my PoV is influenced by the fact that I'm content with Chrom being a Roy echo, but still,
Also, in "IP ressurection projects no one expected":
