Third party software is going to be your answer to the problems you listed above with the exception of the Freezing Up/ Blank Home Screen. That is simply Windows Mobile having issues which generally tends to happen to most of us at least a few times per week.
As far as a firmware update, T-Mobile is pretty good about keeping their devices updated, but the only real changes you might see there will be improved battery performance and less freezing.
For calendar functions, why not just sync the device up with Microsoft Outlook on your computer and do all your date entry on your desktop. You will not be limited by pre-defined calendar choices on your PC.
If you are a heavy text message user, take a look at Extreme Text - Windows Mobile Threaded Texting.