Good stuff and thanks Backdorslider. I appreciate the candor. I don't think that my son has ever used the word "dream," that's more my verbiage and used interchangeably (probably incorrectly) with goal. The end of his playing baseball will be a sad day but it won't be the end of the world for him or for his mother and I. We're just enjoying the ride while we can. The game has provided so many positive experiences, and so much joy, that he will carry with him the rest of his life that there is no way any regrets could overshadow that, even if it ended today.
Maybe I should have been clearer in my initial post that when I refer to "mid-tier." I'm not talking about mid-tier D1 or mid-tier D3 or whatever. I'm talking about the kid who maybe isn't the second coming of Bryce Harper but is a solid top/mid order three or four year high school varsity starter, conference standout in a good conference of high enrollment schools, who is smart, hard-working, motivated, coordinated, and coachable. I'm talking about my kid basically which is why I started the thread 
There is somewhere for him but it is hard, if not impossible, for me to be objective because I see what he keeps up with - how hard he works - all the events, uniforms, practices, games, 6am workouts, tests, quizzes, AP class load and homework, volunteer hours, fundraising events, tutoring, private lessons, cages, tee work in the back yard, coach emails, camps, showcases, etc. etc....and this is at 16 years of age and he's been carrying that on for two and a half years at least! So of course I think he's the greatest thing ever. There is no way I could have done all that at his age so I'm just trying to be there for him in whatever way I can. I'm a proud dad no matter what he decides or how all this works out! I just appreciate all the advice and suggestions I've received from this post. This has been truly inspiring, encouraging, humbling, and informative. Thanks folks!