The URL http://192.168.2.3/admin/api.php provides a great summary of Pi-Hole statistics. However, there are other sensor information that can be easily included there for a more comprehensive summary. The ones that I am most interested are memory and CPU temperature. Since, both pieces of information are tracked by Pi Hole anyways, it will be great to include the same. Thanks!
Those indicators are on the brink of being out of scope, so adding any more in that area would definitely be out of scope. You should look for a program such as RPI Monitor to get your device's system information.