ngsm13 - Your retaining wall is beautiful!
Ohio State is your land grand university. I have included a link. On the left hand side there are links for trees, shrubs and flowers and for landscaping.
Hopefully this will provide you with some usable information.
I had an active landscaping business for 10 years. I had to giv it up after a bad accident. I still do consulting work.
These are some basic tips.
Get a large pad of 1/4" = 1' scale of grid paper
A 1/4" scale plant template - if you can not find it at an office supply store check a University book store. Let your fingers do the walking and call around.
Architect's scale - a 3 sided ruler with multiple scales.
Draw your base plan to scale. Make note of column positions and windows. Also water and electrical supply.
Research plants. The size of your home and the setting calls for a more formal approach. I would love to see a SMALL ornamental tree in the bump out on the left. Another option is a large shrub that can be pruned into a tree shape. IDK if you can grow Loropetalum in your area. If you can it is easy to cut back side growth and train a central leader into a tree shape. The purple foliage is beautiful year round and the hot pink spring blooms will take your breathe away.
When you add plants to your drawing draw them in at mature size. Use odd numbers and stagger the plantings. Mother Nature does not do straight lines.
Purchase nursery grown plants in 3 to 5 gallon containers. Skip the one gallon containers. Even with larger containers your bed will look "skimpy" when you first plant. Don't worry - it will fill in!
Research soil prep on the Ohio State web site.
I HATE weed barrier/Landscaping cloth. If you are not adverse to chemical work Amaze or Preen into the soil before planting. Read and follow the package directions for application.
Pine straw is the BEST mulch for both weed control and moisture retention. Since this is a more formal bed put down a very thick layer of pine straw - 12". Let it pack down then top dress with a thin layer of wood mulch. Cypress or hard wood - not pine bark - it floats away.
What about irrigation? Look into micro systems with a timer. Inexpensive and easy to work with. I always used Poly Drip systems. IDK if that is available in Ohio. Their digital timers have a 5 year warranty. They have a wide variety of heads from drip systems to spray heads that can be adjusted to different spray patterns. The systems available through the Big Box stores are decent. Because of the size of your bed use a 3/4" feed line instead of 1/2".
The time and effort you put into your retaining wall is obvious. It is beautiful. Put the same time and effort into planning your plantings.
BTW - when you plan the bed leave "pockets " for seasonal annuals.
You have a great start!