As for the graphics cards, they'll certainly help speed up rendering time, but it likely won't affect the time taken to pose and create the renders as that's the more involved part of the process. But it'll still be beneficial for them nontheless.
Well, I can see new graphics cards help (or influence) in several ways, accounting for his time to pose:
1. I would assume that posing an animation takes longer than posing a static (say, just for the sake of the argument, 10x the time), but rendering would take even more time (like 100x that of a static render). So while he could be in a position to do 10 fewer statics but 1 more animation in terms of his development time, but doing so (on a larger scale, like 200 statics for 20 animations) might result in too much time for rendering. New graphics card would help with that and allow him to have more animations for (relatively) less statics.
2. I would assume that longer animations take more time to pose, but again with a increase than rendering time. Say 1.5 times the posing time but 2 times for an animation of double length. Thus while he might be able to pose 2 long or 3 short animations in the same time, 20 long animations might not fit the rendering time budget, where 30 short animations do. Again, new graphics cards would change this and therefore allow him to have more longer animations at the expense of (relatively) fewer shorter animations.
3. Better graphics cards with more memory might allow for more complex scenes with more objects/people in them or more intricate lighting or other effects, both for static renders and animations, though of course more complex scenes would take more time to pose. Still, this could lead to (relatively) fewer but more complex scenes.
4. Also, I would expect his time available for posing to go up in the future, if he needs to do less new minigames and phone features (I guess that might be coming to an end) and improves on his speed in posing. So he might be able to do more statics and animations and with new graphics cards, he might have the additional rendering budget to actually do those.