Summoner: if summoner is the first new class to be released what would you expect?

[Duelle]

I don't follow, you can beat any current content with any tank/healer/dd setup you want if you aren't terrible

Ranged still has an advantage over melee. That one still needs to be addressed.

Diversity of abilities. For example in FFXI you have Buffs (Garuda, Fenrir), Healing (Carbuncle), DD (Titan, Ifrit etc)

Balance. I am afraid it will be OP, then shafted with the nerf stick.

Depends. Tanaka & Co. were scared to death of summoners in FFXI because they never placed heavier restrictions on things like switching avatars. They tried to discourage it with summon MP costs and variances in perpetuation and then favors, but the playerbase is very thick-headed and never picked up on it. If you make it really painful to switch avatars, you suddenly don't have to nerf everything out of fear that players will swap avatars faster than they change underwear. I'd use something like the mechanic for Terestian Illhoof, but with player-character detriments instead of just taking more damage.

Say that Evokers can keep their avatar out without having to pay perpetuation, and instead spend MP to use avatar abilities as well as abilities they gain from the presence of their avatars. The avatar dies, and the Evoker gets hit by a debuff called Broken Pact that prevents the summoning of another avatar for 3 minutes and reduces all stats by 25%. Dismissing the avatar and trying to summon again within 60 seconds also grants this debuff.

Then at lv30 when you get the Summoner crystal, your first learned ability is Natural Order, an ability that allows Summoners to switch avatars without penalties once every 3 minutes, but it HAS to be an avatar that follows the elemental cycle of the previous avatar (so if you have Phoenix out, you'd have to switch to Shiva as the elemental triat goes from Wind => Fire => Ice). You can justify making avatar abilities stronger across the board under such design, IMO.