It's what you expect from free software
> the default widget/plasmoid behavior
Generally the defaults for a piece of free software is whatever the author considers will evoke the maximum number of "Oh, cool doood, that's freakin awwwwwwesum" comments within his/her support group online friends. That's what most of them are in it for: the squeals of admiration from fellow geeks, not the silence that comes from well designed software that works intuitively with no fuss and zero learning curve.
So sure, you CAN change the defaults, if you can find where they are stored, and you can work out from the undocumented source what they do, and they aren't hard-wired into the application - which can only be rebuilt by gathering together dozens of obscure (and inter-dependent) source libraries from the 4 corners of the world - and installing all the languages they are written in AND their own sets of dependencies. But really, who has the time to futz around at that level when there's STUFF NEEDS DOING.