Gunter Schelfhout <no.mail@please.com.invalid> writes:
>Ok, since I am still in the design phase, it's probably better to keep
>things separated as much as I can.

It is not even required to keep it separated right from the
start.

You also can have some »dirty« code parts in the first version
where data processing and UI interface code is mixed and
refactor it later to get the separation. Not everyone is so
perfect that he can write it all separated from the start.

Between sessions of coding to extend the set of features,
there always should be sessions to improve the quality of the
code without adding new features. Nobody can write everything
in the best possible way the first time. But one will
eventually not be able to maintain the code anymore if one
never refactors it to improve separation of responsibilities.