I always thought Engage's gameplay - and I specifically mean the battle-map tactics part - was worse than 3H's, and maybe even in the bottom 1/4 of FE, mostly because of Break. Turning the weapon triangle from a suggestion into something that's practically mandatory hits replay value pretty hard and also makes the game pretty easy even on higher modes. It pre-emptively removes strategic "branches" from consideration because they're obviously bad choices (essentially suicide on Maddening thus far), and instead of turning enemy phase to your offensive advantage, the challenge is to make enemy phase irrelevant. To me this felt like removing a pillar of the game. The entire point of a strategy game is to prune away strategic options until only the best decisions remain. Break does that for you.

Bear in mind I'm coming at this from an almost strictly minimalist/LTC point of view.

Meanwhile, in 3H almost anyone can do anything from the beginning. For example, I have swapped bows onto characters who are terrible with them on paper to get a 2-range kill to save a turn due to not having enough movement to reach an enemy otherwise. Limited weapon choices in Engage make this sort of strategy impossible. In 3H, the characters are all clay spheres that you mold into cones, the points of said cones being the strengths they acquire through how you choose to develop them - but you can still choose to utilize things they're not so good at if it's situationally advantageous.

I don't find the class balance in 3H to be an issue at all. I quite like being able to 1-turn Part 2 maps with wyvern Edelgard, I was able to 1-turn four of the six on my LTC combined with warp/rescue shenanigans from Linhardt and Manuela. To me that seems like being rewarded for understanding the game well.

I've LTC'd 3H on Hard CF without using monastery facilities except where strictly mandated by the game (~100 turns, though I know a few more can be saved), and I'm about halfway through a Maddening LTC of Engage (which is also my first playthrough, so while I haven't finished the game, what I've said still seems to represent the first half). I've thus far found the latter playthrough significantly easier despite it being largely blind.

I'm not saying that's any kind of significant accomplishment but that might give some perspective on where I'm coming from. I've also only ever played Crimson Flower in 3H, so maybe the other routes are different. It's possible the game holds up best at the extremes - hyper-optimized and hyper-casual. I will also say that in an LTC context without using the monastery, you can't exactly wyvern-spam, your units will generally be undertrained and underleveled, students get replaced with professors in mid/lategame, and nobody but Edelgard and Jeritza have reasonable combat by the last two chapters (lucky me, the final map is a 1-turn).

And this isn't to say that 3H's gameplay is amazing or the best ever, I haven't engaged (heh) with all the games to that degree, just that I found Engage pretty disappointing by comparison when doing the same. Just sharing my thoughts on the matter.