The written speech was certainly well done, however, the speech delivered was not exactly as written. I know any criticism of Mr. Trump will be taken badly, but in a serious foreign policy speech, he needs to tighten up his delivery.
There is no real place for the sidetrack into bragging about how good he is at deal making because he wrote The Art of the Deal which was the all time best seller. Also, his all too often use of the phrase "Trust Me" comes across almost like a used car salesman trying too hard to sell a lemon. Also, his heavy focus on money takes away from an argument based on principal.
I would suggest that you print a copy of the written speech and read along as you watch the tape of his delivery. He is getting better but still has a long way to go. In the general election, he is not just going to need to appeal to the true believers and if he is elected, he will not be dealing with people easily impressed.
He does have to sell himself to people. He's being torn down...his brand is being diminished...by Republicans, Democrats and the media. So at this stage he still has to counter the propaganda against him...close the sale. Using words like "Trust me" and building up his skill sets and accomplishments is something all politicians do. It just sounds different coming from Trump because his accomplishments fall outside of political accomplishments.
Once the deal is closed...when he's elected President...you'll see a different approach.