I belong to ranchi. And I can tell you bettee than others. Ranchi is good hill area where many types of fall. Jonha is most safe and beautifull fall and it near to ranchi.
Now a days there were huge picnic spot are available in ranchi or near ranchi. Such as hirni fall, jonha fall, dusam fall, hundru fall, etc etc.
There is also a lots of temple where you can prey for god. Such temple are jagannath temple, dewri temple , pahadi temple etc .