@jB07
What could possibly go wrong with time dependent pushes?
Just because something could be done does not mean it should be done.
Far better to somewhere have one or two modifier buttons.
When you push the modifier as well as the main target function it changes what it does.
Actually you do not need to add anything.
Just take the existing soft keys and use some of them as modifier buttons.
Then you would need even less of the other soft keys or you could enable a lot more functions with them.