Opaca, vomitoria, decidua occur here naturally. Not sure if this is what you meant by named but let me know if this helps.

I was going to suggest a landscape rose, but you might not have enough sun. Have you considered another grass, such as blue oat grass or a Deschampsia? Neither require a huge amount of sun and the blue oat grass is evergreen. I am surprised that you thought the Pennisetum to be messy. It does like a lot of sun, so maybe its related to that.

Yaupon is borderline in upper zone 7. Some cold years it can freeze back. I do not believe it is native to Long Island, but I could be wrong. Goodness, for zone 7 there are SO very many hollies that are better looking than American Holly. Fosters #2 is nice, fast, good berries. Smaller leafed. Nellie Stevens is the default holly planted here. Takes shearing very well, but does get TALL. Look into 'Mary Nell'. Incredible leaf gloss and BERRIES, oh so many berries most years. 'Blue Maid' is a nice very hardy blue holly which grows slowly to 12 feet. It takes its time and will not need much pruning. Castle Wall is a very upright grower. (another Blue Holly). Chindo Viburnum might be worth looking into, if it's hardy in your area. Fast grower, very glossy, no spines. This post was edited by dave_in_nova on Mon, Sep 16, 13 at 9:43

Thanks