PARIS — Celine’s smart fall suits and soft knits would spiff up even the most conservative Wall Street wonder woman. In its show at the Grand Hotel, the Paris house sent out a slew of good-looking gabardine suits with soft fluid pants, long plaid jackets over short plaid skirts and knee-length Humphrey Bogart-style trenchcoats. It was investment dressing at its best — clean, gimmick-free fashion. Even the masculine twists worked — rep ties, flat suede loafers and white ascot scarves worn with black tuxedo pantsuits. Celine’s knits — in warm browns, aubergines and greens — turned up in the form of monochromatic suits and jumpers, many teamed with matching gold-button jackets. There were lots of short skirts and ribbed ski pants, and the long, velvet-trimmed English dandy jackets were worn with black tights and gold-buckled, over-the-knee boots.