365 alternative for a casual Excel user?

Hi all, I mostly use Word and Excel for personal projects and the occasional side task. Nothing advanced, just writing documents and basic spreadsheets. My Microsoft 365 renewal is coming up and it’s around £85, which feels a bit steep for how little I actually use it.

The main thing I care about is being able to open my existing .docx and .xlsx files without breaking formatting. I don’t need Outlook, cloud storage, or all the extras. Just something stable that works offline and doesn’t require a yearly subscription.

I’ve been looking at options like WPS Office, LibreOffice, and even just sticking with Google Docs for simple stuff. Has anyone here switched away from 365 and been happy with the result? Any compatibility issues I should watch out for?

TIA