1. I actually like the "padding"... It looks like a TAB as it should. Also, it helps better tell the difference between the Active Tab and the non-active.
2. I have no problem closing the Tab with the Right Mouse Button. How are you putting your mouse JUST on that "tiny" little space?
Also, WHY are you using the Right Mouse button anyway to close, rather than "Double-Click" to Close Tab, which is FAR easier and faster?
You should request a New "Setting" if you want to remove the space, cause this is actually the normal "default" way Chromium Tabs work, and tabs have worked forever for near all browsers.
I know 6.0 was doing it different, removing that space, but that's an unusual not-normal thing. I actually made a request to have the space as default since that's the default for near all other browsers (if I remember right), then to add a setting for those who don't want the space.