1. Tab context menu may be possible, I'll try it later.

2. Menu position is not possible as the context menu api doesn't have that feature, I want it at the bottom myself :)

3. I'll take a look later for the option to only enable certain features.

Sorry for the late reply because the notification feature for review broke for me. I just updated the extension and saw your review by chance.

Edit: Implemented #1 and #3 in version 1.0.0. #2 is not possible because extension can't modify other extension context menu(security issue).