For fairness I won't rate this game. Not because it's bad, quite the opposite it's the best Dragon Quest game easily and a great RPG. My "issue" is that I got too excited hearing about this game, how so many called it "one of the best RPGs of all time" and even after getting the true ending I didn't get the monumental praise. I feel I've played other RPGs that have done far more interesting things, taken far more risks in terms of both story and especially combat, and have way more detailed and immersive worlds. Granted it isn't trying to be anything too radically different, rather it perfected the Dragon Quest formula, a formula enjoyed by millions for over 30 years, without coming off as a generic retread of its predecessors. Like, I can't overstate enough that it's one fine game that everyone (and I mean everyone) should at least try its generous demo, it just doesn't do much of anything that elevates to "masterpiece" levels for me. It's hard to pin down specifics for me, really the only things I felt it did wrong were it's pep system since I really didn't like the RNG of it and how it's a bit too easy on the base difficulty without those challenge modifier you select from the beginning. Granted that last one is especially bias since to me an easy RPG is an especially boring game but it at least has options to spice it up (even if I had to redo a good 10 hours since you can ONLY activate them from the beginning). To me, it does everything it needs to fantastically, but something that is a masterpiece needs do something beyond that, though this rant is really just a consequence of having my expectations too high.
EDIT: Forgot to mention the music. Even with the orchestral versions it's very weak in comparison to most of the older titles, especially Dragon Quest V and VIII. It says a lot when the only great tracks are the ones from older games. I guess I'd rather have them there then not if the original tracks weren't that good. Still a poor soundtrack shouldn't deter you from playing this game, I still standby it being the best Dragon Quest game.