If you think the popup suggestion window is too frequent or too blunt, you can turn this by setting a suitable value to "Real-time Suggestion Window Delay for" at Typing Assistant main menu.
When the suggestion window is shown, you can press Right / Left arrow key(or mouse right click on the entry) to Show / Hide popup menu to quickly edit the selected entry.
Typing Assistant has two running modes: Skilled Typist Mode and Unskilled Typist Mode. To see the difference between the two modes, please see Typing Assistant help documentation: FAQ >> Question No.11.