SPOILERS AHEAD
I love this game, I do. But after about two hundred hours of playing, I've noticed quite a few things that quickly get stacked against the party. In Mar'Liore there are two enemies (the pumpkin king, and the lake beast) who absolutely shred Mercy and Orus, and there was nothing I could really do to stop this. As I've found a lack of essence to prepare for harder battles with only a constant two party members, which, by that point, essentially get locked in to a playstyle, thus come with weakness' only 2 members of a party can't balance out properly.
I've come to find this game cannot be completed, beat, yes, but not completed fully, due to either
A: lack of essence resources and ("Time") to build up the essence stations. The essence are essential. If you're playing a more essence (Magic) focused build, Earth Essence is so incredibly rare, I have taken every yield outcome, searched EVERY possible area for mining (which sometimes offers Essence). and STILL only could afford 2 lower tier spells by my return to Shiveworth during it's occupation.
Beyond spells, Runes, Potions, and even Weapon Skills, all require Essence, which seem to be VERY rare and low amount.
B: Lack of party members. As I briefed over, two party members cannot properly balance each other. And makes things increasingly more difficult as you start getting further in the story. If you played a tanky Mercy, and had Orus heal, you're missing damage, ect.
I'd like to see trade offs (forgive me if I have missed those trade offs or options to add more party members) The crazy Hillie in Corvhanna, trade off you don't get the second ship, and the crew you can collect. maybe one in Witchdale as well, then cap at 4? Or continue to offer more where you have to decide who you want to join your party.
I absolutely love this game none the less, but those two major options makes many battles frustrating, and some are outright impossible.
Perhaps I'm simply under leveled for the areas, but the lack of proper grind worthy enemies that can't nearly beat you as is, coupled with the lack of healing related spells (the ability to fish and make recovery items are nice, but those can rapidly run out where as Mercy can get a status that regens mp while she walks).