This isn't a short game from what I'm finding. Then again I'm not blowing through the game but taking my time to enjoy the game. I can easily see myself getting 20+ hours of the game due to the pace I'm taking. One has to also consider something when one looks at past Final Fantasy games and their time length. The need for leveling and the combat system in general increases the game time significantly. Padded in to a serious degree. Alter those for other systems (which Crystal Bearers has) and the game time spent on those games are significantly reduced.
You can blow through this game if you wish but you are most likely to miss a number of things from what I can tell in my limited play time. For example if you rush through an area you can easily miss and ignore the background information on that area. It's presented to you as a scroll at the bottom of the screen. You completely bypass the Moogles and the mail they carry, the activities you can do as you find along your travels. Stopping to simply fight and mess around is actually fun and not work or boring as grinding to level up past games were.
I almost bypassed a fishing location completely while playing today for example. I was going to stay on the main path but then I stopped and said I wonder if I can swim so I jumped in the water and was able to swim around. Found a number of chest as a result to. Then start jumping from piece of land to piece of land until I came across someone fishing (who I couldn't see from the path) and was able to do it myself. It wasn't advertised as being there but I had to actually go explore for a bit to find it. If I was rushing through the game I would have never known the guy was there.