When recording pay close attention to your levels. It's not necessary to pin the meters to get a good level. It's actually better to peak at -12 to -6db and always use 24bit for the best sound.
Granted the converters play a huge role in sonic quality but no matter how good the converter, if basic rules are not followed it will be detrimental to the sound. This still applies even if you are only using virtual instruments. Clipping internally is just as bad as recording clipped sounds.
When using analog tape we record the sounds hot (above 0) to get certain sonics from tape saturation that's pleasing to the ear. But digital is a different animal and this technique actually degrades the sound. If your song/productions are sounding a bit sterile experiment with the many tape emulation plugins that's available. Or if you have access to some analog gear feed the sounds to said gear and rerecord into your DAW. Most converters are calibrated to -18db = 0VU.