Teak Oil on softwood

A friend gave me some teak oil he wasn't going to use. I've tried it on some finished and unfinished pieces and am generally pleased with the results. Oil gives a luster to wood that you just can't get with lacquer, varnish, shellac, urethane...

Here's my problem when using teak oil on raw wood. Hardwoods look great. Walnut and maple glow. Not so much with softwoods like spruce and cedar. They seem to get darker and more dull.

Has anyone had different results with teak or any other oil? Is there a technique that I should know before trying it again? Has anyone tired oil on the hardwoods and wax on the softwoods?