Echoes was a big letdown and is easily the worst Fire Emblem released in the West, and that's by a very comfortable margin. But it was a remake and it's not selling well, so it's unlikely that much of its mechanics and game logic makes it into Fire Emblem Switch.
Dang that's harsh! What about it let you down?
Basically all of the mechanics and game logic.
No weapon triangle, the EXP wall characters hit at level 10, the requirement to visit statues to change classes, the barebones map design, the Cantors you managed in the OP, the witches who you can't tell if they'll warp or not, the poor stat growths that amplify the lack of EXP, the Jeddah boss, the sidequests that hardly ever amount to anything worthwhile, the dumb stat growths when you change class which for the most part amount to next to nothing and only reset how much EXP you can gain.
I couldn't manage to finish the game. It starts to get tedious in act 3 before it gets outright bad in act 4 and a bunch of units are so outmatched that they become good for nothing. It doesn't help that characters can only equip one weapon or item, and stronger weapons decrease speed which increases the double-attack rate of enemies. It's as if the game was deliberately designed to be grindy in order to make you spend money on EXP DLC to make it bearable.