Clearly the 990 and 975 are classics, and he can't go wrong with them (I'd choose both over the chukka). But IMO captoe boots (particularly on the Grant or plaza last) are the sharpest looking and most versatile among the choices
Honestly if a shell captoe boot is available, I'd get that over the 975 and 990, especially in SF, where you can wear boots all year. I'm biased but I think cordovan captoe boots are the best thing Alden does. I have them in color 8, black and cigar and would get rid of basically all of my other shoes ahead of those three.
Marlow wingtips and a navy business suit will have you looking better than basically anyone you encounter in a business meeting. I've never tried on the Marlow PTB, but given its last it probably would work very well.
Man, I'm having a tough time holding off on some of these orders... AofC just got a black Alden wingtip boot in that I turned down, and I probably should not buy these Vibergs, but I am seriously considering ordering... I'd rather just get the stealth 3sixteens if they are restocked