Grayedsol

I wouldn't write off the gameplay so quickly. I found that people are immediately disappointed once they realize they can't move their units directly, but looking at it from a different (not fire emblem) angle, there's definitely strategy and fun to be had.
Low rank (0-300 rating) does have issues because new players can be one-shot, but once I left the beginners' arena, I found that many battles were extremely tight and satisfying.
The "swap" spells are a huge deal. Some people don't know, but you can use any spell on any unit or square, even if that square is empty.
If you only have "swap heal" but are about to be hit by an enemy spell, you can heal them to swap places and cause them to get hit by their own attack, winning the trade. I won't say that everything is perfect, but I would just encourage people to take another look. The underlying concept isn't bad, and it fits the mobile platform well, it just needs some more content.
Right now the only P2W is Lyn, she unlocks 4 spells, and I would certainly not call them game breaking. She will also be unlockable normally for F2P after the pass. I really hope they add more content that adds strategic elements without breaking the relative balance or making things P2W.

I've had ambition of the slimes for a year on my phone.
It is really, really, really hard.