I agree with the bit about creative writing, and I would add writing more generally. Gemini also allows dumping in >500k tokens of your own writing to give it a sense of your style.
The other big use-case I like Gemini for is summarizing papers or teaching me scholarly subjects. Gemini's more verbose than GPT-5, which feels nice for these cases. GPT-5 strikes me as terrible at this, and I'd also put Claude ahead of GPT-5 in terms of explaining things in a clear way (maybe GPT-5 could meet what I expect better though with some good prompting)
The other big use-case I like Gemini for is summarizing papers or teaching me scholarly subjects. Gemini's more verbose than GPT-5, which feels nice for these cases. GPT-5 strikes me as terrible at this, and I'd also put Claude ahead of GPT-5 in terms of explaining things in a clear way (maybe GPT-5 could meet what I expect better though with some good prompting)