1) Does this mean I am limited to 15 or less seconds to send videos

?
MMS's have size limits
Or is there some way to adjust settings to reduce resolution or size?
Yes
2) On my enV I have the ability to send a text message to 10 people at once. This seems to be a standard feature on many Verizon phones today. However, is this possible to do so on the TP?
The "TO": section I believe can take more then one, did I ever try this, no.
3) If I am text messaging a Verizon phone, I can go into the "sent" folder and see whether or not the message has sent thanks to either a check mark or arrow pointing icon next to the message. Also, under "message info" you can find the status of the message. Is this information available in the sent folder of the TP?
If a text doesn't go you get a notification to resend or might goto draft folder of pocket outlook.
4) I have always used Bitpim to transfer contacts to and from cell phones. However I feel this method will not work on the TP. I have 300+ contacts containing cell phone numbers, email addresses, notes, and home numbers on my enV. So manually entering then into the TP is not really an option

. How can I get my contacts from my enV to the HTC Touch Pro?
Try to see if you can get bitpim data to export to a format outlook can import, then via activesync you can get it from outlook contacts to TP
I know that the Verizon Store has a machine to transfer contacts. Does this work for smartphones?
Call store & ask, never knew this machine existed.
Also, I read that I need to hard reset the phone when I get it home to speed things up. That would probably erase my contacts. What is my best option?
Wait till a rom comes out that has the bugs worked out, others have disabled touchflo in the mean time.