positionally fixed buttons

-- this idea is for horizontal positioned taskbars, but might be extended to vertical also --

theres always the tendency of buttons to stick to the left

you cannot say a button to stay at a specific position on the taskbar!!

i want for example my excel button to stay at 5 cm distance to the rightmost, or say chrome button to stay always at the centre, etc.

- then the combined/gruoped buttons might also take their place beginning at that specific position...

isn't it possibel?