I like FF7 but I don't think it's the best game in the series! I think it's one of the best and it's a little overrated just because it's most people's first introduction to the series but I don't think it's bad, or that you're wrong for feeling the way you do. 9 is my least favourite but everyone loves 9, it's not that I think it's bad or that I don't particularly like it I just don't personally like as much everyone else does apparently! And I agree, 10 despite the immense amount of hate it gets on imageboards (and Tidus' awful VA) it's still a wonderful game. What really made me love it is not just the characters (which I really like) or the music, it's the aesthetic. It's from a certain period in Japanese game developement when they seemed to be obsessed with summer, vacation and tropical settings. I'm not sure if a term has really been coined for that period!
.. In regards to 8, I have a love hate relationship with it personality. I like the characters, and the story, I just don't enjoy playing it. I can't really say why! Personally, there's no real FF game I actually dislike I just like that one the least when it comes to the mainline classic games. When it comes to XI that's basically one of my favourite games of all time, and I feel pretty confident in saying that up to CoP it has one of the better storylines of the franchise with some really great characters. And, hm. It's hard to really say what I feel about 12 I have an almost kind of disconcerting nostalgia when I play it, it's like that interim period for me when Square was becoming more 'modern' and less Square. I know it's unfinished, it has problems, but anything vaguely related to Ivalice will always have a special place in my heart! Ashe, Balthier, Fran, Basche.. Even Vaan and Penelo are enjoyable for me. It just feels like a game that really defines that transition period and it evokes a lot of emotion for me.. Almost as much as XI! .. I'm not sure how I feel about 13, I want to dislike it (and 13-2), especially Lightning but I can't bring myself to hate it. XIV is an amazing game up until about the end of Endwalker I personally think. I loathe what Square did to XI by using the funds it generated to fix their mistakes with XIV but I would lying if I said I didn't enjoy my 15 year journey with that game. It's just a pity that DT, Square and Yoshi have gone weird.
.. 15, I think the boyband are cute and maybe Nomura's game would have been much better but I didn't really enjoy it. It's okay, I guess? And 16 has a great story, with great voice acting but NOT!DMC isn't for me.