Is SKA not acceptable?
No, not really
"ska" implies an intention to do something.
"kommer att" is a prediction about something that may not be under your control.
One of the alternatives I got, Problemen kommer som växa, is actually not weird at all in some Northern Swedish dialects. Not saying it should be allowed - it clearly shouldn't - but it might be interesting as trivia. :)
Växa means to grow. So in the general sense it means the same thing but probably not a precise enough translation.
Why is it not 'problemerna'?
Yes, that's what i put too and it was marked wrong
Because it is ett problem ;)
What is the difference between ska and kommer att?
Why not hoja (with umlaut on the o)