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So what do wall of these additions actually mean or signify?

[name] Senpai, [name]-ama, [name] onnesamma, [name]-chan, and [name]-san.
Or if anyone has any additional ones, please share and explain.

I understand that. But I am confused on the right usage/ appropriateness of each one.

Okay, here's the rundown:

(name)-san is the same as Mr or Mrs. It's for someone you respect or want to convey politeness.

(name)-sama is like Lord or Lady. It conveys a lot of respect, but can be overdone. Mostly it's used to refer to customers, these days.

(name)-chan: ONLY use this when you're referring to someone who is very close to you or who is obviously lower than you in station by a long bit (an adult referring to a young student, for example).

(name)-kun: generally used to refer to men. Implies at least some bit of familiarity with that person.

(name)-sempai: an upperclassman or senior co-worker.

(name)-sensei: teacher or doctor

(name)-oneesama: that's not really used. Oneesan is older sister, and you can sometimes use it to refer to younger women (say 20's or 30's) you don't know. Oneesama I've only ever heard used in anime. Similarly, oniisan is older brother.

Finally, (name)-dono: a very antiquated form of san. Again, only in anime or video games or literature.

Make sense?

Let me know if you hear any others that I haven't thought of that you're curious about. 3nodding Or if you need some more clarification on it.