I'm not sure what operating system you have, but I use Evolution on Linux. There's also a fork of Thunderbird called Betterbird that I used for a while, but the UI was a little clunky on Linux. 

 It'll be on windows machines. I'll check out betterbird, perhaps it can be better on windows. Would u say the ui is a significant improvement over thunderbird despite the clunkiness?? 

 It's very similar. The primary difference is the amount of bug fixes that have gone into Betterbird versus Thunderbird. It's pretty much the exact same UI though. 

 Don't like Thunderbird. Evolution is good. Geary also pretty good. Depends on what features you need. 

 I'm looking for an easy way to sync all mailbox settings across multiple devices (same acct). I'm also looking for ones with good calendar/scheduling, organization, and automation options 

 In my humble opinion, Spark Mail is the best built application with the most beautiful and intuitive interface available on the market, already integrated with AI resources. (macOS/Windows) https://sparkmailapp.com/ 

 Thanks! I'll definitely check it out. 

 I've tested countless applications to receive and send my emails, I have about 14 accounts, believe me. No app has served me better than Spark Mail, the interface is incredibly intuitive, Apple like. Thanks for the zap! 😉  

 That has a monthly sub? yukkk no thanks 

 Annual.