However, it would never have been possible for me to make Heynote for all of Mac, Windows and Linux, on my spare time and within a reasonable timeframe, without Electron.
Also, the CPU usage overhead for Heynote is minimal. It's one of the apps I use the most, and it's never among the programs that have used the most CPU. Yes, 200+ MB of RAM seems quite excessive in theory, but in practice it's less than 1% of the total RAM memory of my laptop (24 GB).