I wrapped up my playthrough of Final Fantasy Mystic Quest last night with a little over 8 hours on my save file. I spent more time than that playing the game given the large number of party wipes and reloading that occurred. (I think? I guess the game doesn't actually reload so it could keep the clock running when you retry a fight.) Here are my final thoughts on the game:
I enjoyed the final dungeon. It had a floor for each of the elemental zones which was guarded by a souped up version of the boss of the earlier dungeon. Each floor made minor use of the puzzles used in the original dungeon. (Sword to open the special statues, hook shot, falling down pits...) What I didn't like is how they didn't run a full palette shift and upgrade of the monsters from those zones so I would sometimes run into trivial monsters.
The ending cutscenes were surprising to me. You beat the big bad, you save the world, and you have two pretty young ladies who helped you save the world. I'd think the story would have the hero want to settle down with one of them. You know, really celebrate? Instead the hero asks the captain of the boat if he can 'borrow' it for a while. Defeating the big bad wasn't enough adventure for our hero and he sets out all by himself on the open sea. Then it turns out someone stowed away on board the ship to be with him... Was it Phoebe? Kaeli? Turns out neither! It's Tristam the treasure hunter who just wants adventure too. I'm not saying I don't blame the hero. I'm just surprised that the final cutscenes don't feature romance.
The game is _really_ easy. Monsters frequently had instant death attacks (petrification in particular) and those are a real problem for a two member party. Except when I got hit with one I'd just lose the fight and get to try it again. The difficulty of individual fights was actually pretty unbalanced and was really only salvaged by getting to redo a lost fight immediately. To make things even easier apparently a lot of the bosses are tagged as undead and can be killed with a single life spell. I didn't do this so I can't verify the authenticity, but it is what I read.
It turns out you don't need to run the battleground for the Gemini crest. I think it just lets you warp around the map to cut down on a lot of the excessive walking I ended up doing. I wanted to test the veracity of the wiki article I read stating it was mandatory. It isn't. The two pieces of armor you can get from them aren't really mandatory either since they do get superseded by a purchased item later in the game.
The monster AI was pretty good in some spots and thankfully not too good in others. An enemy with a heal spell could be counted on using it every single time there was an enemy below half, which was good. I did run into two enemies that liked to spam sleep spells. Thankfully they didn't intentionally abuse the power they had, though the did sometimes randomly do it. First round sleep both my party. Second round punch one person and then put them back to sleep. If I ever wake up on my own, sleep both people that round. I'm pretty sure they have a near guaranteed victory if they do that (I was underleveled and therefore slow so I always went last each round). It did get boring when they opened with a sleep on both people and then continued to spam sleep for no reason.
I think a mark of a good game is how much I want to immediately play it again. Final Fantasy III, for example, I wanted to try again with a different job focus. I actually want to play Mystic Quest again with the goal of avoiding absolutely all combat that isn't directly needed to advance the story. I want to see just how low a level I can be and still win. I'm pretty sure the restricting factor isn't going to be power level since my buddy can handle everything I think. It's going to be how much experience I can skip by avoiding fights. (Possibly which side treasure I absolutely need to get? Having access to the top end armor could be clutch.)
On the other hand, I had no such desire upon completing a game from the Final Fantasy Legend series. I think that means I should be ranking Mystic Quest higher than them. Is it better than Final Fantasy Adventure? Final Fantasy II? I think the innovation of cycling items with L/R instead of needing to go into multiple menus pushes it over the top of Adventure. I suspect if I'd played the original version of FFII that Mystic Quest might even come out on top there, too. But I don't think it quite has enough to get there. It's just too short, and too linear, and too easy. But I definitely don't regret playing it. It slides nicely into the #5 slot as the best offshoot I've played thus far.