Hm -- now there's a thought.
The DQ series HAS kind of made a tradition of only introducing the class system late in the game, and also having equipment determined by character and not class (DQ3 notwithstanding on both counts), and DQ7 and 9 also make it take a really long damn time to master any given class (9 especially).
Seems like it'd actually be fairly trivial to move the Dharma Temple/Alltrades Abbey quest to earlier in the game -- just access it from a different pillar and adjust the difficulty accordingly. (I remember it being pretty tough in the beginning.)
I've been working my way through 6 and it's pretty interesting just how much 7 is a refinement of it -- same moving-across-two-worlds gameplay, and mostly the same classes. (Course, I'm also playing a remake of 6 that uses the 7 engine, so it's entirely possible some of that stuff is backported and not present in the original SFC version.)
The class system might could use some general rebalancing; it was vast but, again, it took a long damn time to complete any class, and it wasn't always clear what would make a good party. (I will give it one thing over 6: I find myself using my class abilities a lot less in 6 than I did in 7.) I remember it being bitch-ass hard to beat the last boss on my first playthrough, and mostly just LONG on my second.
And the postgame was really quite deliberately unbalanced. You have to grind like 20 levels to have a shot at beating God. And of course there's no save point along the way.