In the tarnsparency Panel there are the blending modes which work on individual object groups or layers
and you can also give each object transparency as well.
You mightwant to create a highlight or some kind of reflection.
I am sure you can do better than I did I used an Effext>Styklize>Feaher to soften theedges of the highlights though often highlisht are no soft.
1.) Are there any blending modes like Photoshop has that may make it look better?
2.) Does my use of the Pen tool sound correct?
1) You may create a copy of the path, change the H(eight) to a (much) smaller value in the Transform palatte/panel with the upper centre Reference Point chosen, change either or both colours as desired, and Object>Blend>Make.