I generally don't think too much about my shower soap/body wash scents, but hand soaps and shaving soaps are a different matter.
Lavender is good. Wild lavender/spike is more "manly" smelling, spicier, but I like English lavender, too.
Citrus w/ a nice rich base is good. Lime & spices, bergamot & cedarwood, that kind of thing. tangerine & vetiver.
I personally like vanilla scents, including sandalwood & vanilla.
Bay Rum is nice and manly
Wood mixtures - teakwood, cedarwood, sandalwood, some pine scents
Oakmoss, fern, etc.
Personally I like other fruity scents, mint, spices, pretty much any kind of citrus - but I don't think they are particularly "masculine."
Thanks,
Eric