You don't have to get in to custom filters. Assuming you have one category defined then you just need to set the Severity or SourceLevel that you want to log. It sounds like you want to set the SourceLevel to Information
which "allows Critical, Error, Warning, and Information events through".
In config this would look something like:
<categorySources>
<add switchValue="Information" name="General">
<listeners>
<add name="Formatted EventLog TraceListener" />
</listeners>
</add>
</categorySources>
In terms of best practices there is no one right way. Usually you would probably enable the logging of as little information as required to properly support the application. This will depend on the type of logging you've placed in your application. For most applications this would probably be Information
or Warning
. However, other factors could influence this including current application stability, operational requirements etc.