Thank you for your reply! Have you found any decent alternatives?
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I'd say when you're already familiar with Pico-8 and if you like JS (or even TypeScript) you should check out Tic80. The free version is already quite feature rich but the pro version ($10) also allows external Code-Editor like VSCode which enables you to use the Tic80 TypeScript template and exporting to a standalone game.
Its still limited like Pico-8 but way less than that. With its "Fantasy-Console" nature you obviously have all tools in one environment.