I've never been a huge fan of TP -- so I'd enjoy seeing the investigation of alternate systems being applied to other classes. I do feel TP makes gameplay sort of like a "waiting game" but it really depends on how responsive 2.0's systems are. With 2.0 so close, I can't imagine any radical systems being changed this late in the game.

For instance, lets assume Summoner is going to be implemented. How is the pet going to be mediated and how are the Summoner's spells going to be mediated?

I'd really enjoy seeing a pool of runes mediate the pet abilities. Ie: Carbuncle has a starting rune pool of 5. With upgrades via leveling and talent systems, it can be increased to 7. The runes naturally regenerate over time, and each skill Carbuncle uses takes a varying amount of runes. So, Carbuncle's basic healing move on a party member would take 1 rune, whereas a party wide heal would take 2, a basic attack take 1, and aoe attack take 2, and "super move" take 3-4.

I think there are ways to implement the aforementioned example into other classes and jobs; thus increasing diversity in gameplay (rather than relying on a TP/MP system for everything) and making classes/jobs more unique and gratifying to play.