Hello Olger,
Some simple answers.
1) It's worth it if you are passionate about more than just applied computer science. Everything is getting "SMART" nowadays but without the user it's worth nothing.
Read this (if you havn't)
https://www.saxion.edu/programmes/bachelor/applied-computer-science/course-content
and ask more specific information. Maybe even check out the school during the open day (29th) if you get a chance.
Dutch and international classes are separate. However depending on how social you are, you will find friends independent from someone's origin. That's worth a lot in my opinion.
2 & 3) Cheap accommodation near the university as you see it is doable in terms of 10 km cycling and having 2 or more flatmates.
Then you are able to share costs for energy, internet and food. This will cost you at least 150€. The city as a citizen is quite expensive but student associations will come up for it.
Hope that helps.