I respect your decision to not make it your goal to become a world-class professional speaker. It's okay, really. But I do want to leave you with a story of a young man who was quite similar to you. Many decades ago, he was in college and had to take a public speaking class. Public speaking really wasn't his thing, and he certainly didn't consider himself to be a natural-born presenter. Sure enough, he went through the course in the way you would expect. He slogged through and got a C. (I guess you could say his teacher considered him good enough to give a "pretty good presentation.")
The funny thing is that this same guy went into a career where he had to speak a lot. And then one day he went to Washington and gave his "I Have a Dream Speech" and went down in history as having given the greatest and most influential speech of the 20th century. So if you think of yourself as only capable of giving a pretty good presentation, then you are in good company; Martin Luther King, Jr., was also in the same boat. There's nothing wrong with giving a pretty good presentation, but you already have all of the innate skills you need to be a great speaker.
Good luck with all of your future presentations!