Why doesn't exist yet? and why not a button(Only) for each tool? (See Tool Section at the IDE)
What do you say? Would not be great to have the Serial plotter button already?
Comment down below!...
I use the keyboard. No need for buttons ;)
I don't think Serial Plotter gets used enough to warrant a button. I use File > Preferences, Tools > Manage Libraries..., Tools > Board > Boards Manager, Tools > Burn Bootloader several magnitudes more often than Serial Plotter. There is certainly room for a few more buttons, but not enough room for all of them. Ideally, the IDE would have a customizable UI so we could each choose our own configuration. I'd likely do away with the button bar altogether in that case.