I also just played around with filters, thanks a lot for this helpful post!
While doing some playing around, I found a way to better organize multiple RegexFilters without concatenating them with OR.
<Filters>
<RegexFilter regex=".*Systeminfo_.*" onMatch="DENY" onMismatch="NEUTRAL"/>
<RegexFilter regex=".*CPUUtilization_.*" onMatch="DENY" onMismatch="NEUTRAL"/>
<RegexFilter regex=".*Nightscout_.*" onMatch="DENY" onMismatch="NEUTRAL"/>
</Filters>
By wrapping RegexFilters inside the Filters tag, they can be combined.
Note that the onMismatch has to be set to NEUTRAL. If set to ACCEPT, the other filters will be skipped.