I just redid the island in my front yard last year, and made it bigger this year. My suggestion for your focal point would be a dappled willow. Here is a pic of mine
{{gwi:58402}} Its not a great pic, but I LOVE this tree. Acutally its more like a bush. It dosen't get too big and the leaves are white and green, and the new growth on the top is pink. It looks really pretty swaying in the breeze. when mature it kind of hangs over like your evergreen bush in the pic. I have mostly daylilies in my island. They like the full sun, and would definitly makeyour garden "POP". Heres some clump pics of Daylilies that I have found. If you pick dormant varieties, they will do well in your zone. they are reliable performers, and come back fuller and prettier every year. I do have these in my garden, but mine haven't bloomed yet, so I don't have any pics of them yet. (Just for example)
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I probably have about 50 different ones, and never get tired of them. Ok, here's one more pic I love from my garden of my siberians and dianthus next to my willow.
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Hope you pick some nice things for your island. I had fun with mine! -Jessica

first of all your flowers are gorgeous....actually i have a question,is that a house or mobile home you have in your pictures??? the reason for asking is my home looks almost identical to yours and i love how your home looks..

I don't know why, but the first thing I thought of looked like this:

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I'm sure the other folks on this board will give much, much better creative ideas. No one wants a monster on their front lawn.

I think I would put a garden bench in there with stepping stones to it, maybe include a water feature with it, and just finish filling it in with my favorite perennials.

Ok, I know this thread is a bit old, but it's almost midnight, I'm exhausted, slightly sun burned, and a bum knee from yard work/ planting all day...and I have to tell you that monster in the garden made me laugh out loud.
Quite the sense of humor!
Thanks for the much needed giggle.

how about a conifer collection with an assortment of texture and shapes and colors and heights? Looks like with full sun they will be happy there. And the bench idea is good. It will give a horizontal line to mimic the horizontal lines of your house.