Hi, Cat. Just a peep from the other side of the country. You don't have that much space in my opinion, but it sounds like you love the color of flowers. I'd definitely add a hydrangea or two over by the wooded area, unless that's used for football or something. Tons of varieties, but I like the old traditional types the best. You can easily find info on controlling color of bloom by controlling pH with epsom salts, etc. So you end up with white, purple, blue or pink in varying hues. Yes, they can get huge, but that leaves you tons of flowers for cutting fearlessly for the house (July 4th if white and blue) and drying for wreaths. The fresh blooms you take inside will often grow roots as well (start your own nursery or Mothers' Day gifts). The more you cut this back at the end of bloom time (in freeze areas the blooms stay on to protect the plant), the more gorgeous flowers you'll get next season.
Were I you, I would get some lovely hanging baskets to inject color into your little patio area. Likely there are a few spots that catch enough sun for petunias, geraniums and the like. Fuschias like shade and can easily be over-wintered in your area. You can get hanging ones, but there are tree forms as well if you train/prune them that way. I have HARDY fuschias that are big, prolific shrubs---again, for your wooded area. Not overly fussy about the conditions, and need NO CARE at all unless they get too big. Then prune them back. They won't care. Blooms on the latter aren't big, but the shrub flows in the romantic manner of the Cottage Garden.
I invite you to do a little container gardening so that you won't be stuck into anything during the off season. Do you have a little area isolated enough to "hide" things until their turn comes around? The point is well taken that you will need some tall things at the back of the beds. Some raised planters (Do you know a "handy" man? Or woman, for that matter?) at the back could help you out there. Some of the old faithfuls got that way because they are cheap and easy and COLORFUL. I don't think you're a brand-new gardener, but by all means, experiment with the tons of pony packs they sell everywhere, even the supermarket. Don't be scared to rip out things that die or disappoint. That's the fun of it. Experiment! Hostas will love your shade---use lots of slug bait, if pets permit. I like mine in pots so I can shift them around. Lots of varieties here, too. Some more bluish, which I find appealing, and some with deep ridges, which add interest. Impatiens love shade, many colors, and you can pinch and make your own starts just by putting in water on your window sill. Cat, this is the time of year when we gardeners get all excited. Everything springs into bloom, but BEWARE. The good old summertime can be bleak. Be certain that lots of the things you purchase specify that they are summer bloomers, NOT just spring. I almost got sucked in today by a heavenly little perennial flower that smelled divine. But, although perennial is what we want lots of, spring only is not. Dusty Miller is that frilly white plant you see as filler in beds, and also in cut flower arrangements. Cheap, easy, perennial, and even has a bonus of small yellow flowers. Some people remove the flowers, though, out of personal preference. Don't forget ferns. You may even have some growing wild on your land that could be transplanted. It's such a great texture. Try to get an evergreen variety if there are some that thrive in your area.
Cat, sorry to go on so, but this can all be so overwhelming. Take a few notes with you when you go to the nursery, maybe attempt a little sketch, then go to the garden store and look for bargains! A true gardener can be frugal, because Nature is abundant. Best wishes.
