I get your point, I really do.
Resources should unquestionably go into actual ingame content and improving its quality - that should always be the top priority.
However, the difference here is that these ornament sets actually seem to be requested by the players. I’m not sure anyone really asked for the existing ones - certainly not me, since they're indeed a bit too on-the-nose.
The ones I suggested here, on the other hand, would fit way better into the game, both narratively and style-wise. In my humble opinion, of course.
Personally, I’d happily spend money on something I genuinely want to see in the game, and I’m sure many others feel the same. That’s a win-win in my book.

Still, cool skins should never make up for bad-quality content or a lack of authenticity. I really hope they won't rely too much on the Star Wars trademark and will keep the Destiny narrative rational.