Adding features probably increases the number of bugs, but security updates generally reduce the number of (exploitable) bugs. So I think that not taking security updates is throwing the baby away with the bathwater; stay on Win10 as long as you like, but apply the security updates.
>>tomsme+(OP)
You can actually block feature updates and still allow security updates on Windows 10 through GPO (Win + R, gpedit.msc). Pretty cool and somewhat little-known feature.