Serious question, what's wrong with Thunderbird? I've used Eudora, Netscape Messenger, Thunderbird, Outlook Express, Outlook up to 2016, Mail, Gmail, Squirrel etc etc. I use Outlook where I _have_ to, but TB is a constant across all my systems. IMAP support is great, search is fast, I rely on Google to filter spam. Thunderbird is one of those apps that doesn't need extra work or new features, it just works.
It's slow, it takes a crapload of resources and it has a bunch of bugs I've never been able to fix. If I click the unified inbox on my laptop, I get a blank view, even though there are emails in the sub-mailboxes. This has been going on for years, and I haven't been able to fix it (short of deleting my profile).
