Would you rather have good execution or good themes?

I usually have a preference in well-executed stories in anime and other entertainment I consume, and that's what makes me like them. Granted, that the shows I watch are stuff I handpick and I almost never go in a series blind, thus they usually suit my tastes.

While I do appreciate deep and complex themes, I can't really enjoy them much if they're pretty clunky. I like Eva for what it is, but I rated the series a 6/10 and felt that it only got better at EoE because it was better delivered. Same goes for Parasyte, where it addresses things like humanity's cruelty, but I couldn't really enjoy the ride all throughout because of the plot holes and character contrivances.

I understand that the themes are beyond the story and that's what makes some shows really stand out, but I couldn't really fathom the concept of abstract storytelling if it means sacrificing its structuring.

So yeah, would you prefer an anime with good execution but fairly average themes, or an anime with bad execution but with stunningly complex themes?