I see an awful lot of people bailing on Hard at Conquest 10. I can only recommend that you all stick with it. It's a roadblock, yes, but clearing it cleanly is one of the best experiences in the series, and it's a turning point where you pick up so much EXP and weapon levels with your party, and learn so much about the mechanics, that it doesn't get much harder from there. Finishing it is the point in the campaign where you have a good amount of class/weapon diversity in your party and also an emergent core of heavy hitters, both of which put you ahead of the difficulty curve as you move on.
- Observation: always checking skills and accounting for where the enemy AI might close in for a dual attack.
Something I will say very strongly in favour of Fates is this: with so much information on the table like guaranteed supporting attacks and the Dual Guard gauge, unlike past games (even easier ones, like Awakening with its same-turn reinforcements) I'm never made to feel like I've been screwed by RNG. Every mistake I've made has owed itself to poor observation. It's something you don't notice until you think about it, but it feels amazing.