Overall I loved the game. It managed to connect with me emotionally way more than XII or XIII did, so that's a win in my book. Here are my ramblings for anyone who's interested. :)
World: I really feel like they tried to bring back the feel of the older FF's, but obviously on a realistic scale. Wandering around exploring, traveling by car listening to classic FF songs, Prompto's pics, camping, cooking, I loved all of that so much. I like that the dungeons had an actual sense of danger and were treated like events, each with their own unique dialogue. More legit towns like Lestallum and Altissia would've been nice though. It's a damn shame we didn't get to see more of Tenebrae.
Battle system: Probably my favorite in the series. I never got tired of warp-striking, and I think they did a good job of making fights feel realistic. I liked being able to have companions use techniques. It may not be the same as full control but I was fine with it.
Characters: I think Noctis has become my favorite FF protagonist, and Prompto is one of my favorite overall FF characters as well. The bros have great chemistry together, and the journey aspect of the story really helps foster this. The villain is fantastic and imo the best since Sephiroth, though I feel they could've been fleshed out more. For me, the characters themselves are half the story, and it's lucky that I enjoyed them so much, because...
Story: It's funny, because the story is what I play these games for the most, but I found myself not really caring about the main story and just having fun running around with the bros. I put it off for so long, then once I finally went to Altissia everything seemed to race by so fast, like the story was in a hurry to reach its conclusion. It was jarring after the leisurely aspect of the open world portion. I didn't have a problem with it going linear, I just would've liked the linear portion to have more cutscenes and better pacing. I liked the train stuff, but I feel like it was used as a crutch to keep from having to show us much of Niflheim. Nonetheless, I thought the ending was emotionally satisfying and fantastically executed.
Right now, my top 5 FF ranking is:
X > VII > XV > VIII > IX
Sounds like there's a lot of post-game stuff to do, so I guess I'm onto that next! :D