You mention it's a passion project. If technology is the center of that passion, then pick what you're passionate or curious about!

If not: the tried but true Rails + Postgres.

Add more things only when needed. For example Alpine.js if a bit of interaction that's not covered by Rails' Turbo. If the need for background processing arises, bring in the good_job gem, and there may be no need to deploy it separately at first.

For hosting I'm not quite sure these days. Heroku may be on life-support, but its feature-set covers most basis.