Faulkner was a fine all-rounder at a time when Tests were few and far between and certainly a worthy choice. But I would not choose him instead of Bruce Mitchell, who, as you have said, was excellent as an opener or at No:3. What Faulkner provides is that second top class spinning alternative and to be honest, I would choose him in place of Eddie Barlow. Barlow had a slight edge in batting, but (despite the pace vs spin comparison, or maybe because of it) Faulkner was more vauable as a bowler. Moreover, with Donald, Proctor, Shaun Pollock and Kallis already in, Barlow's medium pace would probably not be that much called for, while Faulkner's legspin would certainly be a great complement to Tayfield's off-breaks on responsive wickets.

So, if one did a Faulkner for Barlow swap, the revised team would be

1. Barry Richards
2. Bruce Mitchell
3. Graeme Pollock
4. Jaques Kallis
5. Dudley Nourse (c)
6. Aubrey Faulkner
7. Denis Lindsay (wk)
8. Shaun Pollock
9. Mike Proctor
10.Hugh Tayfield
11.Allan Donald

Tayfield was no mug with the bat and so the batting is very strong relative to positions in the line-up right upto No:10. As for bowling, Donald, Pollock & Proctor backed up by Kallis plus the off-spin of Tayfield & legspin of Faulkner would indeed make a formidable attack on any surface.