Post this as a poll and you'll see Houzzers vote for an architect. However, it may depend on how substantial the renovation is and what things like plumbing and vents may need to move. Some architects won't take small jobs. Some draftsmen don't have the skills needed for some jobs. Get references locally for both and see their work.

Draftsman typically draw what you tell them to draw, they do not necessarily have any design talent or ability. They just know CAD or the like.

A draftsman won’t correct your spelling, much less your bad ideas that make for a dysfunctional home. The worst curse of all sometimes is getting exactly what you wanted. Then finding out that you didnt know enough to want better than that.