Clairol makes an Herbal Essence shine gloss that has no color but is applied the same way as home hair dye. I haven't used it but from what I hear, it gives your hair the same healthy look just without permanent color added.
One shampoo and conditioner that I think really worked well was Matrix Volumizing (teal bottle). When I had very short, layered hair I could tell the difference when I used them both (and you probably should use conditioner anyway. It will definitely make the condition of your hair improve). I had a lot of added body and volume after washing my hair. I've heard that volumizing shampoos open the cuticle more and let the hair expand, which might be exactly what you're looking for.