If you are paying based on word count, it's usually a better deal when your text has longer, fancier words. For example, consider a science paper where you might find words like "photosynthesis" and "glucose." These words consume more characters.
So, if you use 1 token for 400 words, you'll get more value from longer words because they take up more space. On the flip side, if your text has shorter, simpler words like "cat" and "tree," you can fit more of them into the same space.
Therefore, using 1 token for 3000 characters would optimize your value.