Who should be Trump's VP? Well, what are you looking for in a VP? First, someone that will help you win an election. Second, someone who can take over if you are unable to finish your term(s). And, third, someone who is close enough to you, that the VP will follow your policies fairly closely.
A bad example for the third rule was George H.W. Bush for Ronald Reagan. After President Reagan finished his terms, Mr. Bush turned his administration to a "kinder, gentler" tone. However, he may have been a good choice for reasons one and two above. I'll leave that for you to ponder.
Now, what does Mr. Trump need. Someone who will fill all of these three qualities. He can look for Midwest swing state help, someone to energize his base, or reach out to broaden the base. The key for doing these is to make sure he doesn't compromise his current base, who might think he's selling out and then they stay home, which is a key to the third characteristic. Someone currently serving, or who has served in the Senate, the House, or as a governor helps prove that the candidate can easily take over.
Many good names have been mentioned. I would look for a good candidate who is young enough to take over eight years from now. My choice, and I realize there are many other good ones, but my choice would be Steven King of Iowa. He is an immigration patriot, and a leader among them. He broadens Trump's base because he was a Ted Cruz supporter and would help bring in some of that camp, and yet he still energizes the base. He is also young enough as a congresman that he can take over in eight years. There are many other good choices such as Kris Kobach or Senator Sessions, but I think Rep. King would also help bring in his swing state of Iowa.
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