suggestions for a specimen tree?

I am looking for suggestions for a small-ish tree to be used as a stand alone specimen tree adjacent to a short wall of my house. I'm thinking about the Autumn Brilliance serviceberry or one of the crabapples. I'd love to have something with interesting bark. Flowers are ok, but not if they are pink (I already have three pink flowering crabapples in my yard). I really like the shape my other crabapples are taking, but don't want to repeat the same tree. Does anyone have any thoughts about another crabapple that would have white or red flowers, or maybe interesting bark? The site faces the SW, gets a lot of afternoon sun, but I have drip irrigation available. I'm in zone 5. Any suggestions would be appreciated !

How about a stewartia, if they're hardy in your zone? Beautiful specimen tree, 15 - 35', depending on species. Flower white in summer, great exfoliating bark.

I agree, nice bark/winter affect, nice flower, available locally.

I'll throw in some non-pink flowering species for the bark-ophiliacs:

Acer spp. including A. griseum, A. triflorum, and any of the stripe barks
Chionanthus retusus
Cornus mas
Cornus officinalis
Syringa pekinensis

I'd lean towards growin's experience on ultimate size of the species listed above.

Most of the crabapples are selected for great flowering, fruiting, foliage, and form; I can't think of any selected for interesting bark.

Thanks for the suggestions! I should have mentioned that I live in Zone 5 - hot, dry summers and cool winters. Not alot of snow, but the temperature can dip down to -10 for a few days in January. And oh, the wind - and this site would get the worst of it! Now that I've thoroughly challenged your imaginations ..... I did quickly take a look at the stewartia but the hardiest I could find was Zone 6. Any experience with this tree in windy conditions? Any ideas about the best foliage and form crabapples that are not the Prariefire cultivar?

I used to have a Sargent's "Crab". It has small very red berries that remain on the plant. During the winter, when Cardinals run out of tastier food they pick them off.
Candymint grows in Alfred Maine.
http://davesgarden.com/pf/go/80711/index.html http://davesgarden.com/pf/go/126298/index.html

Oh, the Stewartias won't survive there, sorry. This may be a bit "out-there" but have you ever heard of a Siberian Salt tree (Halimodendron)? I've heard of them grafted on Siberian Peashrub for a nice, extremely tough small tree/shrub with purple flowers.

Don't want to twist your arm on the Stewartia, but that came to mind to.

You might double check that. Are you aware that they grow in Portland, and that temperatures there occassionally drop into the teens? Hopefully they don't see 0 again, but that was about 60 years ago.

The dry continuous winds in your area might matter for that.

Are you game for a conifer like Arizona Cypress 'Blue Ice' ??