I would like to propose an idea to your reports. May be you could create a basic report that counts only the total open, closed, waiting, locked, and total tickets, you may include other statuses your ticket has. The ticket counting is simple just count all open ticket within specific period of time and other filters. Counting for other statuses would be the same, just count base on their status no other criteria. Existing filters are good and should be implemented with this.
I hope you consider this.
It would be much better if you let us decide which field should be shown when generating reports. I mean custom report that is being done by end user (us).