Have you thought of a Hebe? I know it is a bush rather than a tree, but will add interest all year and you can prune it to control size. An Acer I don't think would like the position near a road and that is the only one I can think of, although a winter flowering cherry would grow big in the garden! you could control the size in a pot. Excuse me thinking out loud. lol.

any of the dwarf conifers would be good too. there are several of shrubs, acuba, skimmia, osmanthus, holly, eunymous, bay, box, rosemary to name a few.

Blackcurrant sage would be lovely - mine flowers from May to January and the fragrance of the leaves is super.

Also a magnolia Stalata (sp) but you might have to prune a bit as it grows! they are lovely though.

Magnolia stellata isn't evergreen, though....

Hebes are - as Maggy said, or how about Viburnum tinus or Choisya ternata? They all have flowers as well as being evergreen. C. t. 'Sundance' has yellow foliage if you'd prefer that to green leaves. There's a variegated form of V. tinus, too.

Dodonaea viscosa 'Purpurea is a large shrub which may suit the bill, It grows tall and is evergreen with pink flowers. It is a member of the hop family but not as invasive. They are hardy and I grow them in my garden, I would recommend it.

Oh forgot the evergreen bit SpitzH the Viburnum is a good choice lovely winter flowers.

Andrea - I love that shrub, but sadly, it wouldn't be hardy enough for an open position in Cleveland. Your environment is different, lucky you!

Do you have one Spritz? I think it can withstand temperatures as low as -15 c, so it may be ok in sunny Cleveland.