Hm, I'm not entirely sure where to begin with this.
As i stated in the flare blitz thread, you can get away with sometimes throwing it out until the Lucario is above 60% without an AS charged. After that, you're asking for punishment. Also be aware that a properly redirected Double Team counter (If the Lucario holds away from where you came from during the animation he can kick you in the face instead of from behind) will absolutely decimate you, so Flare Blitz should only be used as a surprise or to seal a kill or punish a read IMO.
Lucario has a fast grab game and his various ranged specials can really be annoying given zard's speed. He also got a movement speed buff in 1.1.3, so
he can approach you better than before. Jabs probably outrange lucario's but there's always force palm and good lucarios know how to pressure with it.
Flamethrower sounds like a neat idea, but you may only be making him stronger and giving his force palm and aura sphere more deadliness and range.
.... I honestly wouldn't know where to begin fighting my own main with zard.
All that being said, his air game is pretty neat but his weight makes it somewhat easy for zard to gimp him into oblivion, provided it connects. That recovery is nice, but only if you're not already slammed into the lower boundry. This could be really hard to pull, though. His up air can be murder at higher lucario percents(it's actually one of our bread and butter kill options) and comes out faster than zard's dair, so watch for that. His bair is also in the same category for kill options.