Most of the best reggae stuff is recorded very clean and simply mixed. Don't get fancy, let the instruments speak for themselves when it comes to the width and depth. No need to get too fancy with the drum mix, just grab it cleanly and make sure you get a good snare and that the toms don't sound dead.
It might be best, IMHO, to think of reggae as high-fidelity blues. Keep the mix technique simple like the blues, but give it the high-fidelity of a fine orchestral recording.
The bass git can be very important in reggae, get it clean in the tracking and make it prominant in the mix. Don't be afraid to bring it forward.
Once you have the rhythm down solid on your mixing desk with prominant bass and punctuated drums, lay what you have left with the arrangement simple. Reggae tracks usually have as much dead space in them as they do signal; rhythm is king, noise is not. Let the dead spaces breathe. Let the dead air in the steel drum be the window frame for a few guitar fills, and vice versa.
This doesn't mean that the music itself has a simple arrangement, some reggae recordings with a ton of instruments has some very complex stuff going on. I'm referring to the mixing approach. Keep that simple. Give each instrument it's space both on the soundstage and in the spectrum. This doesn't mean that you can't use delays and reverbs or set up a stereo wall backing with your steel drum, but it does mean that you should proably do so sparingly and not set up any walls of sound using layered tracks with heavy panning and delay or anything like that - the exception being perhaps for one instrument that you want to dominate the mix (even then, make sure it does not cover the bass), or for special effect on a sparsly-populated rhythm track somewhere. Keep the reverb simple, use for mood more than for special effect.
The important thing I think is the spectral fill. Track and EQ to give each instrument it's space in the spectrum. Every instrument should be a different color, and you should evenly populate the spectrum from 20 - 20k as best as possible. The bass should be prominant but clean on the low end, with everything metal from steel drums to hi hat being crisp and defined on the medium-high end.
G.
