I thought the whole point of the Trump presidency was that he wouldn't implement any policies, just use his position to promote his companies, use Twitter to shoot down every policy anyone in Congress tries to pass, and see how long it takes before the Republicans get sick of it and impeach him...
Seriously, though, for me it's not really about what scary policies will he implement, because considering everything he has shown about his campaign as well as the leadership style described by his employees, he simply doesn't have the vision, the determination or the interest to design and implement any particular policy - at most he will inspire one (and torpedo others). Obviously he has some basic ideas that he campaigned on, but just about every aspect of their implementation seems to be negotiable and to depend on the last person he talked to. To the extent that significant and lasting policy changes do occur under his presidency, they will be driven by a combination of his cabinet and the Republicans in Congress.
What he will do, though, is cause offense and sow division on a daily basis both within the US and outside it, which both the US and the world really could do without, without doing anything very useful to compensate.