You need to remember that creating a new job takes them 1 year, and even though redesigning SMN wouldn't take that long, it would still take a very long time.

It could also piss off the players that actually like SMN right now, and maybe just want some additions in the expansion.

I do agree that their spells doesn't make sense really... but I would still like the job if they added the right spells.

They could still change SMN at least towards the way they should be. First off all, they could change the egis, because at least that isn't 1 year worth of developing, and our carbuncles became egis, so why couldn't our egis "upgrade" further in the SMN quests to look more like in FFXI.

Second, they could add some ability/abilities that directly affects our summon a lot more than just spur and rouse. Can't really come up with ideas right now, but there are many options. Maybe you could reduce your own damage for a duration, while your summon's damage goes up drastically, enough to make it worth doing. It would put more focus on the summon too. It could maybe solve some burst damage problems too.

If they focus all the new abilities and traits on what summoner should really be, then they could make a big difference