Actually people use moa - specifically red - because it's ferocious and has frenzy strike which synergizes with relic of fireworks, useful for proccing One Wolf Pack during bursts, and overall does pretty solid damage compared to kitten like chomp or tail slap. Trust me, I'm not picking a moa for the 1k hp heal on a 10+sec CD, its for the slaps. The literall only reason nobody uses smokescale in PVE is the forced movement and general bugginess of smokescale assault.
As for "Takes a lot of time to do" - the attacks are already in the game, and animations can all be re-used from other attacks or professions. Hell, literally they can use the same animation for ferocious screech as harmonic cry or a warhorn skill. As someone with dev exp unless there's some massive spagcode in the backend, an intern can get it done in under a week.
Lastly, the point is to make the pets more compelling and for reasons to take pets other than moa, rock gazel, jackaranda, or iboga. It adds style, panache, and an overall sense of polish that I think would drastically improve the pet system and add a reason for the average ranger to go out and "catch em all"