For overall opinions...
Putting aside the similar parts, the Grimoire system is better in this game. Each Grimoire can only hold ONE skill now, but characters can attach more than one Grimoire. You can also trade and recycle Grimoires. By recycling Grimoires, you can slowly build up to a Level Star (10) Grimoire, and then by using that, can trade for any other Level Star Grimoire.
The Force skills have all been fixed and downgraded from the original 2. Each character has 2 Force skills, one which lasts 3 turns giving various effects and then 1 powerful one that, when used, "breaks" the Force gauge, preventing you from storing Force until you return to town. However, when you return to town, your Force gauge automatically fills up to Max.
So anyways, 1st Stratum:
The intro map to FOEs, as you move in circles(?) to avoid the intro FOE, the deer we all love... or hate. Like the original, the occasional appearance of the caterpillar causes accidents, because of its high HP/power.
Intro to a new gimmick. A trap floor that opens up when a FOE/Boss stands on it, trapping it for several steps and decreasing its HP. Even after the FOE/Boss escapes the trap, their HP remains depleted and they also move slower on the map.
Not much new, just a lot more using of the trap floors.
Rocks block the path around the floor, though the FOE on this floor can ignore it.
Boss floor with everything from the previous floors combined. There are two bat FOEs in the boss's lair, but if you defeat them first and go back to town to recover, they remain defeated, It is a lot easier than throwing bombs in battle every turn, so you might as go ahead and take them down.
The Boss's lair, as you can see, has several trap floors in it. You can actually get the Boss to go through ALL 4, lowering his HP 4 times and even can attack from behind. Rather, from his large amount of HP, it is probably wise if you do so.
In Story mode only, the Paladin NPC will join the battle with you... But you already have a Paladin, so kinda of meh there.
The usual deer. He has two skills, one that does heavy damage to one target and one that causes confusion to one target. If you can survive the damaging one and use the Princess's skill to prevent confusion, it should be easy to defeat. His special drop is easy too, finishing off with a Slash element.
The replacement(?) for the flying FOEs in the original EO2. The design of the original still exists as monsters though, BTW. It appears after the deer, but he is easier to defeat. His Blood Suck skill does hurt, but not as much as the deer, and the recovered amount isn't terrifying either. His weakness and special drop to the Stab element makes him easy pray to the Ranger's Force Break.
He does have a Head binding skill, but since both the Princess and Doctor Magus can recover, it shouldn't be too bad if only one does. Of course, the Ranger and Paladin aren't really affected.
The dinosaur FOE that existed in the original.He can cause Paralysis to one target, but other than that, mainly brute force. But you can drop his HP and take his back thanks to the trap floor gimmicks, which gives your party a nice handicap.
-Piercing + Poison
-Hit to two characters
-Defense down to all party members
Thanks to the trap floors, you should have a good handi. To avoid the powerful poison, try to have the Princess keep her Order (that prevents status ailments once) on the entire party. The Paladin might want to use Front Guard instead of Fire Guard because only one move is Fire and while most of the others can be blocked by Front Guard. Other than that, keep pounding away. Weakness is Ice, Special Drop is to take him down with Poison's damage.