Etrian Odyssey series is by far my favourite.
Battles you thought you had lost can totally turn on one simple move, often one that 'feels' like it makes sense.
'Oh man I'm screwed here if I take one more attack... What if I took a chance at binding the head of the main spell-caster so that the other one spends a turn casting a spell to unbind it and have the rest of the party link fire attacks to see if we can do enough damage to the melee enemy to take it out, even though that will leave two of us without MP... There's only a medium chance the bind will hit, and if it doesn't I'm done, but if it does....'
When the plan comes off you feel like a genius. When it fails it's agony. Figuring out what enemies are best fought in what ways is fun, too. Or what about when you're down to two characters left and through clever use of healing abilities, MP management and items you get your entire party back on its feet... amazing feeling.
It's always interesting, always fair, and leads to balanced fights. It's basically the opposite of the useless 'Simon Says hit the weakness' Press Turn system.
Surprised at all the Xenoblade mentions. It's only half a good system - what you do as the player is fun, but the enemy / encounter design never really makes any interesting use of your options at all. 90% of the game is just going through your rotations the exact same way. At least Melia is fun to play, whereas in XCX no one is.