While I understand that Kibana does a lot in the browser, as a sibling commenter said, I think there's much room for improvement, performance-wise.

I use fairly basic stuff in Kibana. I practically only use the discover panel with a reduced number of lines. It's by far the slowest webapp on my computer. Granted, it's a 2013 MBP (with 16 GB though), but pretty much nothing else is so painfully slow. It's barely faster on a more recent computer (i5-8500 with 32 GB).