You could get a
fatso
Or on the lower end, you might consider an ART Pro VLA.
Honestly, though, I don't know if you're going to get what you want out of a compressor or a mic pre. Lack of warmth I generally think of as being a result of bad microphone selection. i.e. -- using a mic with a noticeable high end boost on something that doesn't need it. Or using a condenser where a dynamic or even a ribbon might be more appropriate.
The source and playing technique play major roles as well. Bashing the crap out of nasty-sounding cymbals or overly-aggressive strumming on an accoustic guitar as if you're mad at it . . . are good ways of making things sound "not warm."
The list goes on.