I'm personally quite happy with using the Chrome extension to create a task from an email in Gmail. Maybe that integration could be deepened to keep track of replies or other activity inside ClickUp? My inbox is a very different beast — I would never want to bring that monster into ClickUp in full.

Yeah I really like the idea of using this as my primary email. I would get rid of other clients if this had a calendar.

As part of Gmail would be great

or alternatively, deep integration with gmail including android / ios clients would accomplish the same goals, without requiring writing multiple email apps?

Couldn't this be accomplished by including email account configuration using IMAP protocols. It wouldn't be the best email experience, but just as good as iOS mail app, and helpful way to stay inside the clickup world. Also could permit a better email to task experience. I'd suggest adding "Mail" accounts to what is labeled INBOX and allow it. It's been awhile since I've worked with email backends, but the IMAP protocol was configured to cache locally only recent messages, so this wouldn't have large storage overhead.

Also the possibility of true drag and drop to tasks and calendar timeblocking would be huge.

Wow that would be an intense feature... I personally wouldn't really want this because it would increase the costs by a lot for just a select few users utilizing it. I wouldn't switch because of the extensions I need for Gmail

This would be awesome.