surely I can think of something better to write than "cheers"

[darkoshi]

39 ways to close your emails

Some of my favorites from that page, including the comments:

Be well, do good deeds, and keep in touch
Confusion to your enemies
Tag. You’re it
The end (for now)
Up, up, and away,
Ta,
Happy Trails
Ciao for now
Upward and onward
osmosis, amoeba
Have a magical day

Comments

[marahmarie]

Regards - used when side-eying someone I don't know from Adam
Ta - used when I dislike whoever I'm signing off on (usually doubled up with an exclamation point) : Ta ta! (this is the most sarcastic way I can tell someone to screw off, without actually doing so)
Ciao - I really dislike them (multiple exclamation points if they're honestly harshing my mellow)

Haven't used Yours/yours truly since maybe the 90s, usually shorten All the best and Best wishes to Best, and think most of the other suggestions ring hollow or desperate, so I most often stick to Best or Cheers. They sound British and are fairly meaningless, yet common enough.