Fong Ghoul said:
Related question - IX was my first DQ game, and I loved it. Loved all the loot and the job/leveling system, loved the sidequests and other optional extras, story was OK, combat was OK. I think I just liked that there's so much to do. Are IV/V/VI more "standard" JRPG's? Is the combat fairly simple? Is the stat/leveling system the same? Are there jobs to manage? Lots of loot to be sought through exploration/sidequests, or do you just come across it in a more linear fashion?
To answer your questions in order:
Yes, IV/V/VI are more "standard", in the sense that they are exclusively single-player, traditional JRPGs. The structure of the three games is noticeably more rigid than IX, especially if that was your first experience with Dragon Quest and you haven't played many pre-PS1 RPGs.
The combat is similar. Unlike DQIX the battles are random, but you select your actions from a menu (using the standard Attack/Magic/Item/Flee options) at the start of a turn and then watch as the turn plays out. There are different options to speed up the battles if you choose. Also, like DQIX, you can issue simple AI commands to your party (focus on healing, all-out attack, etc.).
The stat/leveling system is not exactly the same, but there are several similarities. Like DQIX, each enemy awards a specific amount of experience points, which aren't scaled to correspond to your level. Unlike DQIX, the experience split among the party members is equal. Besides that, yes, you defeat enemies to collect experience points to level up, and when you level up your stats will increase.
IV and V do not have jobs. In IV, each character can play a specific "role" in the party, alleviating the need for classes. In V, the human characters have specific roles, but you can also recruit a large number of enemies to be in your party. Most enemies have class-like specialties; cureslimes, for example, are obviously geared towards using curative magic. VI does have a class system, albeit one that is more limited in scope than IX. You can eventually create "hybrid" classes, which allow you to combine two classes to make a stronger class.
For all three games in the Zenithia trilogy, loot is not a major element of gameplay, unlike DQIX. You come across equipment and items during the course of a normal playthrough, using shops and monster drops. There isn't a sidequest system in any way similar to DQIX, so they are in a sense more "linear".
All three are certainly worth playing, though, if you liked DQIX. The story for the games in the trilogy is considered by a large number of fans the best in the franchise, and none of the three should require any excessive grinding, unlike the first two games in the series.