Final Fantasy. I love how changing it is. Always exploring new possibilities. XV seems to be the most daring one to date. I had enough of games with narrow horizons and no real progress in term of ideas and visions ( looking at you Assassin's Creed ). BTW that is the exact same reason why the "fanbase" of FF are so damn conflicted.

I'm certain most of the "fanbase" don't really know what they want done with the franchise. Hard to blame them though. the changing nature have messed with their minds.

My favorite JRPGs are Paper Mario TTYD and Final Fantasy IX of course! I am not a huge fan of Sticker Star because it took rid of the humor, charm and other things the earlier games had! As far as FF is concerned, I am pretty indifferent to FFXV! It's looking much better than the entire FFXIII trilogy, but I highly doubt it's going to reach Final Fantasy IX quality-wise!

Square(enix) they should have never let go of pre-rendered worlds.

What in Final Fantasy XIII changed for the good? I hardly call linear gameplay innovative. The combat system was innovative but then they went and made three games all using the same assets, same heroine, and such. It is like they intentionally made a series out of this XIII to cut corners in rebuilding a new story, new hero, and so on. I think its taking a back step compared to what your saying. Even the combat system is similiar in design. I haven't played XIII-3 but at least they made time play an integral role in the game but other than that, I wouldn't give credit for it changing much.

I'd say one of my favourite JRPGs ever is Final Fantasy XIII. It was pure perfection, and one of the best entries in the whole FF saga.

All Time: Final Fantasy, by far. Some of my very favorite games in any genre. But XII was weak and XIII was poor. I have lost faith in them.

Current: Xeno-, by far. Xenoblade was everything FF XIII should have been. It had so much of the old-school FF magic mixed with modern innovation. I really can't wait to see what they do with X in HD.

Change is not always good. I didn't say that. Still, that " linear gameplay" example is irrelevant, it is a design choice, and such choices can not be innovative. It is either linear, semi-open or sand-box. neither is new or innovative.

Spin-offs are clearly meant for easy profit. It is purely business decision as the developing cost are going higher and higher. Still, XIII series introduced tons of new mechanics ( XIII-2) and fundamental design choices (LR) in the saga, they explored new possibilities with each release. XIII was story driven, XIII-2 tried to be player driven ( and failed imo) LR is world driven with continues passage of time and events that happen even without the player being there. 

That what I love about the series, the "freshness" even in Spin-offs.

There are a lot of RPG series that bring new things to the table without ruining them though, even if some may be downgrades.  Arc the Lad 1 > 2, Wild ARMs 1 > 2 > 3 > 4 > XF, Breath of Fire 2 > 3 > 5.  Legend of Legaia > Legaia 2,  Persona 2 > Persona 3.  SMT 2 > 3, Phantasy Star 2 > 4 > Online > Universe(downgrade,) Ogre Battle > Tactics Ogre > Knight of Lodis(downgrade.)

There are a lot of RPG series that are just tas changing with their ideas as Final Fantasy is.  It's unfortunate that Final Fantasy and other Squaresoft titles(because of Final Fantasy) are the only ones that got recognized by most people because there are a lot of amazing games out there that don't have Final Fantasy as the title, aren't from Squaresoft or Enix or even Atlus published.

Yes. Though Lunars situation is a bit more precarious. The last 2 entries in the series were quite frankly, bad. The latest one was a remake of the original that lost the fast battles towards a slower paced gameplay. It made the game quite difficult to stomach.

So, the series has fallen not only on sales but in quality, and i dont see how theres any room to bring it back now. :(

Too lazy to edit, but to answer you question about Wild Arms. There is a chance that Sony might bring it back. Media vision is now working on the PS3 shining title for SEGA, but Sony can choose to use a different developer or grab them once they are done with Shining resonance.

There was some Wild Arms DLC on Soul Sacrifice delta, so its clear that Sony is saying they havent forgotten about the series and are probably gauging interest.

Well Final Fantasy is still my favorite series and that series has been all downhill since FF9 and before that they released one of the most overrated games of all time with FF 8.