The peak of Price was about 1976 to 1982, roughly corresponding to seasons 4 through 10, and here's is why it was the best era for the show:
Just in time for the hourlong conversion, the set was brightened with its second colour scheme, which was definitely the best it ever looked. A palate bright and easy on the eyes, and never colour overload or a bad mix of colours. Walking was introduced at the beginning of the calendar year as the "come on down" cue, and it punched up the enthusiasm more than the original cue employed.
The best single word I've found to describe this era is electric, and this is largely through Marc Breslow's superior directing. Shots were fast, tight and full of action, whether that be fast-moving graphics and titles, sweeping dolly shots or quick cuts in rapid succession. Dig up something such as a win in Any Number around this time, and what happens? When that winning digit lights up, bam! A shot back to the contestant reacting with delight, then a shot of the contestant's friends in the audience, then back to the contestant, then a shot of the car, then a shot of the flashing price (and probably no less than a total of six or seven quick shots in a matter of ten seconds). Then the contestant is escorted off and we see the Turntable spin away with that flashing price and a fully-lit board as Barker pitches to commercial. So. Much. Energy.
And on the subject of energy, the contestants. My goodness, most every woman called was nearly hysterical as she jumped out of her seat and darted down to Contestants' Row, jumping into the microphone and frequent squeals of, "I can't believe it!"; and the contestants in these years were sharp. All four might bid within seven seconds. None of this turning around a looking at the audience (something Johnny openly discouraged in his warmup, and how I wish that was still done today), and the show never had a low opinion of contestants who watch the show everyday and memorized the prize rotation and prizes but openly encouraged the loyalty (and it's not as if anybody broke the budget for trying). Barker was also in his finest form of bringing out the best in each unique contestant (overly stereotypical at times, yes, but in the whole of the Barker era, this was as good as he got since he was also not sneering at contestants, as would become the norm by the mid-'80s).
Speaking of unique, the Showcases were properly recognized as the ultimate part of the show; and Jay Wolpert with the weekly Flakey Flicks and other elaborately-staged, long, thematic Showcases and employed some true creativity. Some of the best recurring themes were established and used throughout this era.
The prizes were especially elegant in this era (if not sometimes a bit unusual). No shortage of sponsors, and they knew how to make a prize sound special. When a Cadillac was revealed in a game such as Golden Road, you were in for car plug of nearly 30 seconds with at least 11 different options ("and California Emission"). That's elegance.
I also like how car games fourth were not necessarily unheard of at this time and how cash games could replace car games, given that their prizes were worth more than most cars at the time.
By 1982, the glory was fading fast. Breslow's directing was getting slower. The contestants were not of the same calibre as they were previously. Barker's ego got in the way that furs were no longer offered as prizes, and he also turned into a curmudgeon that I can't believe went unchecked. A lot of contestants deserved to be chided for foolish behaviour, but Barker was downright nasty at times for no good reason. While it was only downhill into the '90s and beyond, I do want to note that there was a brief renaissance around season 33 when Roger became the sole producer that lasted to the end of the Barker era. Roger started injecting creativity back into the show, whether it was zany lineups (and not just to spoil the FPG) or some long-overdue Showcase themes that were far more creative than Phil Wayne's "wordplay" Showcases that were dull and overused.
And I haven't even touched on that parallel, alternate universe that existing at that time which was The Nighttime Price Is Right. From the glimpses we've had of it, it seems it was just as, if not more, impressive; and I hope we shall continue to get to see more of these glory years of The Price Is Right, daytime and nighttime.