A Leitz Focomat IIc is never wrong. Just see to that you get a fairly modern version. Given you live in Holland, which is really close to Germany, these machines should be easy to find at a decent price. There is a guide somewhere on the 'net where the different versions are described.
Else, maybe you can find some version of a Durst AC or maybe M which takes 6x9 negatives. The larger Durst machines are very well built too and readily available in Europe.
Both the Durst and the Leitz are condenser lens enlargers, which give very crisp sharpness, but maybe also somewhat more retouching. I would personally never even consider using a softbox on my Focomat, but that's me.
What's a softbox in this context? Do you mean the Ilford 500 diffuser box? I don't understand.