The problem is that I can't spend hours and hours trekking through a final dungeon and grinding towards victory.
Okay, so why not just make all dungeons a little shorter, punchier, and well designed (You know. No mazes, no "switch-flipping hell," no endless, double-backing corridors), get rid of grinding completely, and either switch to a save-anywhere system or let the player make quick saves? That way you take care of the tedious final dungeon problem and a whole hell of a lot of other problems at once. And if you HAVE save points, increase the number of them.
The goal of the game is to be challenging. The goal of the game is NOT to be abusive.
At that I'd also advocate adding something like in Dragon Quest where, if you die, you lose gold but keep items and XP.
And I'm starting to get the impression that 'bad final dungeons' is just a symptom of a greater underlying problem with the genre, now.
Also, I feel strongly that final dungeons should have relevance to the plot and maybe even be an integral part of it. Does it really hurt to have cutscenes in a dungeon?
Why stop at a cutscene? Get rid of the cutscene there, and take a cue from SHMUPS and use other visual elements to convey story. The most basic example, maybe, is to have something like cave paintings on the walls revealing important information, but it could be done really elaborately.
See the problem with cutscenes in a dungeon is that they're often non-skippable and by definition non interactive. So, you die, repeat the dungeon, and you have to do the thing again.
Then again, if you have a savepoint after every cutscene, DO make them skippable, and uh... yeah. Then it's not as much of a problem.
Finally, no dungeons should EVER be a point of no return. Points of no return are almost always atrocious game design.
Give me puzzles,
OH, right! Another good point. FFXII didn't have a lot of puzzles from what I remember -- very non-interactive. Comparing DDS to Nocturne, I also felt those games had few puzzles or interactive bits -- especially the second -- than Nocturne.
Although I think it's fair to say that dungeon design is the most neglected aspect of RPG making. I think you could argue in the past that dungeons in most games were intended to do nothing but take up time. I personally think they should be more like playgrounds where you kill things.