Can someone explain party play and leveling efficiency?

[Alhanelem]

How have these changed, if at all. I hate the fact that everyone seems to indicate you solo till ~35. Can you duo? Is that all there is to do till 35?

You can party with as many people you want as any level you want and it will work just fine. But soloing the early levels is easy enough that people don't often bother looking. You can solo all the way to 50 if you want. This game doesn't force grouping on anyone.

At level 35 Thousand Maws of Toto-Rak becomes available; most people just farm it for seals at lv50 but if you want a fun challenge you can do it at the level for which it was designed. There's also the low-level caravan escort and the main scenario, and the first Job quests are available at level 30.

call me old fashioned, but I really like the one mob per pull days of FFXI,

Don't know how anyone could like this. It was an excruciatingly slow and tedious method. Even at the time i didn't like it that much. It was the quests, story and endgame events that kept me playing, not the leveling experience.