I realise you might have something more complex in mind, yet recommend first being sure that you understand your maximum room for action within the available more straightforward parts of Swiss inheritance law.

For anyone else reading this, and not sure how it works, here's a nice illustration of the percentages which go to each heir.
https://www.berghilfe.ch/was-sie-tun...CAAEgIocvD_BwE
From the list on the left, select your currenty family set-up. Click "Weiter", bottom right, and it'll draw you two pie-charts.

The left-hand pie chart shows what happens if you die intestate. The right-hand one shows the extent to which you can reduce the heirs to their "Pflichtteil" (obligatory, protected inheritance). Once you do that, the remainder (shown in turquoise as "frei verfügbar") is yours, freely available to distribute as you wish, including allocating some extra share to one of the heirs, or leaving it to any other person or organisation of your choice.

In your case, OP, with partner and children, with that simple step you could therefore leave your partner 62.5 % instead of 50%, or the other way round.