Question Are Travel Planners Really Helpful?

I'm planning to travel to Germany in April and I'm considering using a travel planner to organize my trip. I need a complete travel plan, which should include accommodations, transportation, and must-see attractions. For those who have used travel planners before, how was your experience? Did it make your trip smoother, or do you think planning everything yourself is better? I'm curious to know if the convenience is worth the cost.