Usually, the best way questions often get viewed as being too opinionated/subjective like you said. But, if you look at our "avoid asking" help page:
Some subjective questions are allowed, but “subjective” does not mean “anything goes”. All subjective questions are expected to be constructive. What does that mean? Constructive subjective questions:
- inspire answers that explain “why” and “how”
- tend to have long, not short, answers
- have a constructive, fair, and impartial tone
- invite sharing experiences over opinions
- insist that opinion be backed up with facts and references
- are more than just mindless social fun
Personally, I would consider your particular question as more of a strategical question on how to best use this rare resource, and strategical questions are on topic:
- Gameplay strategies and tactics
One other thing you may want to consider is changing your question to be more definitive. Maybe instead of asking "the best" thing to spend the resource on, you could ask what are all the things you can you spend it on. This may indirectly answer your original question, while also being less opinionated.