Thanks for the prompt and informative responses!
Most of Iowa is cold hardiness zone 5. So your foundation plantings will need to be cold hardy and shade tolerant. You should consider that you will be creating some shade gardens. That is nice because shade gardens can be beautiful!
Here's a thread I did about cold hardy shade perennials for someone who was also in zone 5 (Indiana):
viewtopic.php?f=5&t=68596&p=388903&hili ... ns#p388903
another shade garden picture
hostas and painted ferns and wild ginger.
Along with perennials, you will want a few shrubs to anchor it and give some height variations. Shade tolerant, cold hardy shrubs include azalea and rhododendron, oakleaf hydrangea, virginia sweetspire, daphne (but be careful not all varieties would be cold hardy for you), mountain laurel, hollies and junipers, red chokeberry. You might even want a small tree for the corner of the house opposite side from the driveway, like a dogwood or redbud.
I would think about using the whole space between the walkway and the house as a garden space and then make a garden on the other side in front of the whole section of the house to the left (in the picture) of the porch and curving out.
Unless you have a ton of money, you are going to start with relatively few and small plants and shrubs and a lot of bare mulched dirt around them. In a couple years they will get a lot bigger and you can keep adding more. Keep things small enough/ low enough not to block the windows or the view of the entry way. Think about putting in a bird bath or other small water feature, as in the pictures in this thread
viewtopic.php?f=8&t=69527&p=393646&hili ... ns#p393646
One easy way to get some height without blocking windows and without having to spend money on a big shrub is to put a small shrub in a big pot. Mixing some containers in with your ground plantings gives nice contrast of height, textures, etc.
Look for a good nursery (NOT big box store) that carries a lot of native plants. In return for you making a fairly substantial purchase, they will be glad to consult with you about what grows best in your area, design suggestions etc.
Get to work now! You have not much more than about six weeks to get whatever you are going to fall plant in the ground. Maybe just plant a few things and add more in spring. Or maybe just work on getting your soil ready (and figure out your design plan) so you will be ready for spring planting. You are going to need to till up the ground where your beds will be (a half a day's work with a rented rototiller) and put down a lot of good soil amendments: compost, composted manure, worm castings, shredded fall leaves, etc.
So that's a lot of information and a lot of threads to read. Let us know what questions you still have after you have read and thought about it. Best wishes, it's a fun project. I'm going to be doing the same kind of thing at my house this fall.