People misinterpret Fan service quite a lot.

Fan service- Take the best things that had the most reception and incorporate into said project.

Taking things here and there ( IE: Crystal tower, Odin, etc) there is nothing wrong with it at all.

If you think its wrong, then putting in Chocobos/Airships/Summons Shouldn;t be in their either because it's "Fan service". Don't give me the it's a FF Staple c**p, because no matter how you put it, it's still a fan service of some sort, because the "Fans" love Chocobos/Airships/Summons etc. Mandies/Couerl's. Aplukka's (sp?)... Point is, people tend to use Fan service it further make the point to put the idea in a bad way.

Anyways, Showing off a girl Chest SE likes to do with their offline FF titles, "That's true Fan Service", What Yoshida is doing is a good thing, Bringing all the FF games together (practically) is something no FF game has done, and I admire the idea, ( As long as the lore make since with world lore. Then I'm all for it.