It depends on what it is, but on average Google Drive share-links (with our without expiration links depending on context). I had been a longtime user of Dropbox but the commoditization of cloud storage caused me to make a price-based decision related to Google.

For work done in Figma, I may additionally send share links to files or prototypes that clients view via Figma in the browser.

For large files or quick sharing, WeTransfer has a great & simple recipient experience.

Yes, Symbol Instance Renamer paired with Organize Symbols are a daily use combo IMO.

Here are the Plugins tagged as 'essential' on Sketch Hunt blog: http://sketchhunt.com/category/essential/

In an Agency-to-client situation where MyAgency wants to manage projects for client A, client B, and client C. I'm assuming the "Team" pricing model will 'just work' and there's no need to hold out for Enterprise unless those extra features are desired - correct?