Ask question in category, then auto select category?

I wish some features below can available:

1. When user’s being at a category page and do “Ask question”, then this category will be selected automatically (at dropdown list).
2. In category dropdown list (of ask form), insert a empty row as default, when user post question without select a category, the notice will appear “Please choose a category…”. It help user can post right category.
3. Customize category more than (background, icon, text color,…).

Please think about this.