I modded my multimeter, roughly following this guide: https://www.jackenhack.com/aneng-an8008-modify-for-better-accuracy-faster-readings/
I used the parts I had, which for the 3V rail were 100nF and 10uF ceramics, and a 470uF Rubycon. The voltage reference also got a 10uF. The replaced cap was a 100uF Chong.
Autoranging is still frustratingly slow, but I think it is probably a bit faster once it’s in the right range.