Is there a way to add a main menu button to the unity panel?
Actually, there is a main menu button on the dock called applications (dark grey lower half) if you right click you will get the typical main menu entries and then the dash format opens. I would be also happy if I could move this "icon" to the top in case I dont remember (happens I am over 50) the name of the app and want to use my graphical memory by switching to classic view (like in windows). Bottom line, the functionality is there, just lets hope a more knowledgeable person will enable us to move this function to the place where we want to see it.
To answer your question*, no. The Unity panel and the GNOME panel are two completely different and mostly unrelated pieces of software.
*please avoid rants.
maybe you will be satisfied with this: http://www.ubuntuvibes.com/2011/05/get-best-of-both-worldsyour-own.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+UbuntuVibes+%28Ubuntu+Vibes%29
ClassicMenu Indicator
ClassicMenu Indicator is a notification area applet (application indicator) for the top panel of Ubuntu’s Unity desktop environment. It provides a simple way to get a classic GNOME-style application menu for those who prefer this over the Unity dash menu. Like the classic GNOME menu, it includes Wine games and applications if you have those installed.
installattion
sudo add-apt-repository ppa:diesch/testing
sudo apt-get update
sudo apt-get install classicmenu-indicator