Generally I feel gentleman's folders should be relatively sleek, slim, and lightweight.
Why not just an elegant slipjoint? The A.G. Russell small titanium folders are worth a look and their traditional designs, while made in China of relatively inexpensive materials have pretty decent fit and finish. For larger options consider a slim Opinel and the Enzo Pk70. Kershaw used to have a nice lockback with polished G10. CRKT has some Centofante designs that might interest you.
Any number of traditional folders would fit your needs. I like the look of the Kershaw Shun Higonokami (often listed as folding steak knife). Rough Rider and various other Chinese knife companies have decent designs and the materials, while synthetic copies of natural materials like pearl or tortoise-shell, do look quite nice. Muskrat, Peanut, Doctor, and Barlow are popular patterns.
One-handed: Spyderco Cricket, Spin, Chapparal, Air. Pretty much anything Mcusta. Benchmade has some Nakamura designs I find appealing. Enzo Birk 75.