Regarding passing on letter/number key-presses to the command line, I'm -0 on this. Note that not only letter/number keys should be passed on.

I've often found myself wanting to type in the command line after looking at previous code, to see that my key presses are being ignored, and having to Ctrl+End to return the cursor to the command line.

However, if I was scrolling through the history and by accident hist a letter or number, having the cursor jump to the command line and the window scroll back to the end would be annoying. Personally, I would prefer avoiding this and having to use Ctrl+End to return to the command line.