The World Models Sky Raider Mach-1 has a semi-symetrical airfoil and less dihedral than most trainers. It makes a great intermediate airplane capable of nice aerobatics but still stable and forgiving enough for a beginner with good instruction.

The Hobbico Avistar is similar.

It sounds to me like you are describing more of a Stik type airplane though.

Also, dihedral isn't necessarily a bad thing but it seems to be a dirty word for some people. Just remember that the designer put it there for a reason and taking it out may gain one thing only to give up something else.