Quote Originally Posted by Bourne_Endeavor View Post
And those links fail to address a significant Achilles' heel to horizontal progression: people min/max. Look no further then FFXI, where people who chose the incorrect sub-job basically had little chance to do endgame content. While you can have small bits of diversity, the moment one job/class/ability outpaces another by enough of a margin, it will be deemed useless. This is especially true amongst gamers today because of Youtube, Reddit and even this forum. People are either encouraged to look at guides or follow advice from veteran players. Yes, you do not need to optimize for anything outside raiding, however people are typically going to get advice from better players, who in turn, have no reason not to say such and such is better. At best, MMOs can have a form of diagonal progression. In fact, most do; borrowing elements wherever possible to shake things up without deviating from vertical progression. FFXIV gets its variance through allowing players to readily change their job on the fly.

None of this speaks to the sheer difficulty of balancing a game with numerous weaving paths. Dragoon currently has 27 ability you will actively use. If every skill offered just two additional options for us to choose, you've effectively tripled the developer workload because they now have to assume every possible combination, lest one setup becomes overpowered. STR tanks are an example of what happens there.
Odd that you pick out FFXI as a counterexample, as FFXI is probably one of the best examples where horizontal progression WORKED. Gear in that game lasted for YEARS, and yet people still kept playing because there was always other pieces of situational gear to obtain that would make their character just a little bit better in those situations.

While you are correct that certain jobs occasionally outshone others, that had zero to do with horizontal progression, and everything to do with SE making job adjustments that shifted the balance, or added new endgame bosses that favored one job over another (for example, NIN tanks were king until SE started adding bosses that regularly used horrendous attacks that ignored NIN's evasion-based damage mitigation).

Your bit about incorrect subjob is also perplexing. If you have the wrong subjob... you level the correct one instead. Just as in this game, you were free to level any and all jobs on a single character, and leveling a job high enough to use as a subjob was a relatively quick thing (I say relatively, because pretty much nothing is quick in FFXI).

At endgame in FFXI, you saw folks in a variety of different kinds of gear, depending on which pieces they'd been able to obtain. Players were not excluded from party because they did not have a specific gear build. It was understood that while every job had pieces of gear that were best-in-slot for specific situations, not everyone had the time or luck to obtain every scrap of BiS gear. There was just too much to choose from, and obtaining each piece tended to be a long-term endeavor.

In the end, FFXI, too, became a vertical progression game, with the introduction of gear ilvls with the Adoulin expansion. But for more than ten years, and over three full expansions they were able to maintain a stable playerbase and never had to increase players' job levels, thanks in large part to horizontal progression.