What essentials would you choose today as opposed to 1958?
Fifty-odd years ago, according to G. Bruce Boyer in his excellent 'Curmudgeon's Lament...' essay, a young man's Ivy League style wardrobe would have consisted of the following items:
six OCBDs (three white and three blue
two or three pair of khakis
Shetland crewneck sweater in any color
pair of brown penny loafers
pair of white tennis sneakers
tan cotton gabardine balmacaan raincoat
tan or navy duffel coat
tweed sports jacket and/or navy single-breasted blazer
grey flannel suit
seersucker or tan poplin suit
dark grey or navy tropical worsted suit
half-dozen ties (regimentals, foulards, or dots)
For those so inclined, he also mentions:
white or tan buckskin oxfords
tan cotton gab golf jacket
madras sports jackets
silk knit ties (plain black or navy, with square-cut ends)
paisley pocket squares
odd flannel trousers
broadcloth tab-collar shirts
cordovan brogues
scotchgrain wingtips
navy worsted pinstripes with vests
white duck trousers
lambswool turtlenecks
camelhair polo coat
striped surcingle belts
argyle socks
I think nowadays a little more variety in the shirts would be normal, maybe a pair of jeans might be in order. And it would all still work in 2058 I suppose.