I mean sorry if this is a very late answer. I used to enjoy Y over X because of the raw stat with (I don't remember exactly) but I think 160-170 special attack. This with drought allows for massive wallbreaking potential. The only problem I see is that with offensive threats such as scarfed landorus-t (rock slide) or a tapu koko with T bolt or wild charge, charizard y gets outsped and easily killed as its speed is only 100. X on the other hand has more boosts as Y only usually runs fire blast or flamethrower and gets the drought boost, X gets tough claw boost on both flare blitz and dragon claw which are usually the most popular moves on it. Also the dragon fire typing neutralizes a lot of weaknesses. Yes it brings back the ground type weakness but at the same time you get immense sweeping and wallbreaking potential. And for Y I recommend timid over modest so you cannot get the most out of the special attack. This is where dragon dance comes in for char x. If you get one you can sweep majority of the metagame. With two d dances you can potentially break through immense walls such as toxapex.
In the end it is up to you but I recommend X over Y.
The movesets I would use for Y is: Flamethrower (for higher accuracy), Air Slash (For coverage, extra STAB and potential flinch hax), Roost (For recovery as Y has fatally low recovery options and needs the extra health or it won't leave for more than a one on one trade), and Solar Beam for insane damage and coverage.
For X (Since I use him on my current team) I use: Dragon Dance (For a lot of setup options and also to easily threaten a switch out), Dragon Claw (Outrage leaves you vulnerable after 2-3 turns which is why it is a bad choice and dragon claw already has a base power of over 100 thanks to tough claws), Flare Blitz (STAB, Insane damage boost and brings base power to over 150 thanks to tough claws), And earthquake (Doesn't get tough claws boost, but allows for insane overall coverage and damage.
Sorry for insanely long answer. This is all of the experience I received on Charizard Y and X every since I started learning about the competitive scene.