Re: What would Guthrie Govan Do ????
The Custom Custom isn't the deepest bass or the punchiest attack, but definitely fat and not harsh. But it isn't squishy and buttery in all guitars, either. I've heard plenty of people get great blues to classic metal tones with them, leaning most towards hard rock. Eddie Van Halen used them in some guitars in mid-80s, for example...
Custom 8 sounds closest to what you want, but it does depend on the guitar. Has nearly all of the bass punch of the ceramic Custom, with highs more like A2... But attack is more towards ceramic, but without the (IMO excessive) present bite. [I don't get on with most ceramic pickups, nearly all have really ugly presence to my ears, but the original, ceramic Custom is one of the least ugly, and probably my 2nd favorite ceramic pickup after the gonzo metal PATB-2 Parallel Axis Distortion.]
For stock pickups, I'd try the Custom Custom, and if it isn't punchy enough, try A8. If A8 is too hot or too deep a bass, there's Roughtcast A5, Unoriented A5, and Roughcast Unoriented A5 (from brightest & punchiest to darkest & smoothest, though all are brighter than A2).
If excess mids are a problem, A5 or Roughcast A5.
The Custom is incredibly flexible platform for magnet swaps.