I have used Kagi since Jan 2023 and it still feels awesome, I try to get everyone I know (who actually cares about this stuff) to use Kagi, I'm a huge fan.
But...
There is still so much to do with the current offerings, Orion is super buggy (I keep trying it then going back to firefox / safari), there are a lot of dodgy sites appearing in Kagi search results, and I ended up here today because I couldn't figure out how to delete all of my Assistant history, turns out you have to delete them one by one!
That said, I use fastmail so I'm no stranger to paying for my email, could Kagi coax me to switch and pay them instead? Currently, its a firm no from me. Assistant has been really slow today, search has been filling up with those wierd sites which scrape Github and Reddit comments and somehow get ranked highly in search. AI slop sites appear faster than I can tell Kagi not to show them to me again, and I'm pretty sure I have been seeing ones I told it not to show me again.
Email is way too important not to be done right. To move my email to Kagi I would need to feel like Kagi are mind reading me with feature implementation, not shocking me that features I would expect to exist haven't been implemented yet.
OP pretty much nailed it with features I would be looking for from an email provider, but I want to add keyboard shortcuts. I like to process my email quickly, a fast UI and keyboard shortcuts are a must.
But please, also look at what is going on with search because it's like whack-a-mole banning junk websites my search results recently.