Dragon Quest is a series that rarely if ever defies it's incredibly typical fantasy setting. Almost all of it is in FF1-4 setting, with about half of them lacking even an alternative interesting twist to them (time loop from FF1, taking down a human emperor and all his forces only for him to take control of hell when he's dead in FF2, etc).
I'm sorry but DQ games are pretty differentiable. I do agree with you on the fact that all DQ games follow the tradition of a medieval fantasy setting but the games itself are quite different.
Lets see
DQ1 - Single party member i.e Hero only. Dungeons can only be navigated with a certain item and spell.
DQ2 - Insanely brutal difficulty. Grindy and yes it is pretty generic, I agree here.
DQ3 - This game came out only a year after FF1 yet the class system is MUCH more impressive and the game overall is very polished and entertaining itself.
DQ4 - Suikoden III's Trinity system like approach concerning the story only it was released over a decade before Suikoden III. The main character for each chapter is the only controllable member in battle and the rest are A.I controlled much to the annoyance of many players including myself.
DQ5 - The first DQ game to have a good storyline. Marriage system midway branching out different storyline segments and characters. Monster recruiting system which allows player to use the charismatic DQ monsters found all over the world map in battle.
DQ6 - Return of the DQ challenge in difficulty. People overlook the fact that DQ7's job system is strikingly similar to DQ6. Fantastic story if you pay attention.
DQ7 - Has a reputation for being the longest jRPG and even after playing over hundreds of them I haven't found one quite as long as this. High challenge. Grindy. A little more polished job class than 6's.
DQ8 - The world of DQ brought into 3D for the first time. Insanely huge world. Outstanding VA, visuals, characters and filler segments. One of the best RPGs of the PS2 generation and the very best of DQ IMO.
DQ9 - Won't elaborate because I haven't finished it yet (more than half-way currently)
You should know that DQ isn't a series for everyone because it isn't. Most if not all DQ games require grinding, some can even be brutal (DQ7 and 2 especially). The DQ games are also quite slow because the main plot is usually peaks only during the beginning, midpoint and end-game. And ALL games in the series is riddled with fillers much to the dismay of many.
But for a DQ fan like me the pros outweigh the cons. Battling every new monster is a treat because their anime-like design is very appealing to me. The fantasy-medieval system, the class system, the exploration and even the cliche bad guys just seem very well done somehow.
Even being a huge DQ fan, I'll admit it isn't anywhere near the best RPG series of all time because there are a few below average games namely DQ1, 2 and 4. And it is not a secret that this series isn't for everyone.
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