While I don't have a certain play style, I never found Zard Y to fit any of my styles. I always preferred Keldeo, Hydreigon (Who sucks this gen in OU) or Gengar (I love the Timid Specs and Life Orb sets) as a hard hitting special attacker. While neither of them hits as hard as Charizad's Fireblast/flamethrower and Solar Beam in the sun, I prefer their coverage and their typing. Zard Y requires a very good support to remove the hazards and doesn't like constant switching in and out. And the other reason, is that I love X so much, that almost everytime I make a new with a Mega Charizard in mind, I forget about Y and pick X. I tried using Y for a Sun team, but Y is a selfish Sun summoner and the likes of Shiftry can't take advantage of it.Care to discuss the pros and cons?
As a favor to me, and as yourself as a team builder, please give Char-Y a shot, he's a gem to play with if you give him what he needs
Indeed, Fire Blast makes him a fierce wallbreaker, but Max Speed base 100 is so crowded that his use of that speed is situational. If I ran timid, It would only be to outspeed things like Jolly Max+ Excadrill, which has become mostly obsolete with the popularity spike of adamant Sand Rush variants.
The fact that Zard-Y can derail the standard SandCore (even with a Modest nature) and function as a decently fast wallbreaker/cleaner makes him very valuable these days, you may want to try him out, experience some scathing Fire Blast misses, and let me know if your opinion changes.
Why Timid? X can afford to run Adamant, because it has a way to boost its own speed with Dragon Dance. While both X and Y play different rolls and X needs its speed to sweep, an extra speed is always welcomed. Timid outspeeds non-scarfed Adamant Garchomp. Outspeeds Jolly Mega Garchomp, Modest Keldeo/ Most 100-110 running Modest/Adamant, outruns max Speed Deo-D (Though not sure if anyone uses speed evs on it) Jolly Lucario (Who can 1ohko with Stone Edge/Rock slide if it caries it. And if it was Sword Danced, it can 1hko Zard with Thunder Punch)
Not all of these threats are relevant in OU, and many (if not most) 101-110 Pokemons run Jolly/Timid. Timid is just a safer option. and in reality, when you have 100+BP power attacks and the Sun to boost your fire attacks,you don't really need that 10% of extra power and you can afford to run the safer option of being faster.
I think I should give Y a try. I currently have 4 new teams that I'm playing with, but I should give Zard Y a try when I make new teams.