There are quite a few trees you could use for a small space. Here are some suggestions for you to consider.

Amur Maple, Globe Norway Maple, American Hornbeam, Eastern Redbud, Golden Rain Tree, Golden Chain Tree, Flowering Crabapple, (Variety Prariefire is a good one), Japanese Tree Lilac (Variety Ivory Silk).

If you have small children, the Laburnum, Golden chain Tree, is probably not a good idea, as the seeds and seedpods are highly toxic.

If you water well, a dogwood (Cornus Florida) is a possibility; you can get white, pink or red flowers. C. kousa might be too pyramidal, judging from the ones I see growing locally. The redbud also comes with white flowers, and in a purple/red leafed cultivar - 'Forest Pansy'. A serviceberry in a single-trunked form might work also. Another to consider is a 'Kanzan' flowering cherry, or a cherry plum (P. cerasifera). One of the medium sized Japanes maples migh be a possibility, if they would take the winters.

However the height "requirement" is a bit limiting, as most of the above will be more in the 15-20' range (some may be taller), at maturity, which might not be for more than 20 years. Pruning to keep a tree shorter than its natural growth is usually doomed to failure, and the tree doesn't look too attractive, either. You may decide to ignore that, on the grounds that you won't be still living there - it's up to you.

You might do better with a shrub that you can limb up into a tree form. Several viburnums, such as possum haw, or black haw or nannyberry would work, as would a 'Peegee' hydrangea, a regular lilac or a carefully chosen for height deciduous magnolia. They might take a bit longer to grow as tall as you want than a tree would, although I have a viburnum growing now that I plant to limb up - it's about 8-10' inside of 5 years, starting from a one-gallon, 18" size. Starting with a taller/larger plant will give faster results, once it "settles in", which can take a year or so. Or, you can pay for a plant of the size you want now, depending on whether the deciding factor is time or money.