Yes Cliff's total 180 in his personality was awful. They made him evil. Blowing up a platform with people standing on it is bad enough but to continue to do it with your pregnant daughter standing is unforgivably evil. In the original series, Cliff was not a saint but he was not like this.
I have read that Ken Kercheval was not coming back to the show. If that is true, I don't blame him with the way they destroyed his character.
As for Jacobs's idea of making Christopher and John Ross the polar opposites of their dads could have worked it written well. Now that could only work if it were Christopher vs. Lucus instead of John Ross.