Now that I've got my BeagleBone, I'm still not happy :)
I'd like to be able to plug the USB cable into my host PC but not have the board power up. Since the USB cable is now also the serial cable, I'd like to have a few seconds after plugging the USB cable to get my serial port terminal up and running so I can watch the x-loader and u-boot data from a cold boot. Based on my read through the schematics, this isn't possible by just removing a resistor or a simple hack. I could probably cut some traces and solder up some jumpers, but it will look messy and I'm not sure it's worth the time, yet.
It would be nice to have the option of the micro USB connector's power only going to the USB hub and FTDI chip. That way, when USB is plugged to the host PC, the serial port can be set up before the ARM core boots. Then when DC power is applied to the 5V input, the ARM core and all other circuits would be powered and boot would occur. This would be behavior similar to how the BeagleBoard and BeagleBoard-xM work with their "real" serial ports. I could connect my serial term before boot.
I realize I can just push the rest button to get a glimpse of the x-loader and u-boot messages, but that's not what I want. The things I'm going to be building on my BeagleBone will have a rather quick boot (although nothing like the 1 second stuff) and while doing development, I'd like to be able to see the messages scroll. It's also not always a good idea to hit the hard reset button once Linux has mounted the file systems and started services (ext3/4 have journaling but it's still not a good thing to do often).
I'm not sure of the official procedure for requesting hardware changes for the BeagleBoards, but I'll probably stop by the Google Group and post this request there, as well.
EDIT 20111208 6:40am: I sent in a message to the BeagleBoard Google Group yesterday describing this.