Ok why these 2 specific teams? Why not all of them? Does this mean something? A hint to a return in S/M?
It means Sinnoh remakes confirmed.
Although, if they plan on making all teams at some point (fingers crossed!) I think it makes sense for these two to be first. Rocket because, well, do I need to explain? Galactic to align with the 10th anniversary of Diamond and Pearl.
Next could be, perhaps, one of Team Aqua and one of Team Magma. Team Plasma and Team Flare could be after. They may just not want to release six themes all at once. It's usually better to spread these kinds of things out anyways, because if someone can't afford them all at once, they'll probably forget to check back once they're able to. But by spreading them out, people are more likely to afford them all, or at least grab one from each "pair" since there's a gap of time between them.
Ah the artwork on these are fantastic! I really love seeing the Pokemon in the background and the expressions of the Grunts (especially the Galactic ones). Interesting to note one of the Rocket Grunts has a whip like in the Gen 1 games, and despite the Admins from Gen 2 being there, the Grunts are the designs from the Gen 1 games.
I really hope they release themes for all the evil teams! I would love to see what a Plasma one would look like, possibly including all the Sages.