Easy — in the artist class where time was the artist's own and not a constraint, then Laurence Whistler for his Galaxy window, one of those great works that you can see time and time again, seeing something new and amazing each time.
In the artisan class, paid piecework rates, first overall is Mr Douglas' Deer Hunt, Walsh pattern A5263, which is simply mindblowing. I'm convinced that Clyne Farquharson was involved in this amazing design — the earliest Walsh pattern clearly showing his influence. Mr Douglas was paid 8/6 for his work on this 14" bowl.
Then, in the pond category (waterlilies, irises, bulrushes, &c.) Mr Douglas' Waterlily & Iris, Walsh pattern A5231, for which he was paid 9/- for his work on the 14" bowl. My favourite is the amethyst vase in the pattern shown in Leibe & Hayhurst p.38, which hides a surprising secret, just about visible if you approch the photograph with a very open mind. Don't worry if you can't see it — it took me about six or seven years!
Finally, in the floral category, anything by Jack Lloyd, whose fresh and delightful work stands head and shoulders above a pretty mediocre crowd.
Bernard C.
ps — I've not considered anything anonymous, which includes some lovely engraving designed by Keith Murray and others from factories like S&W and Webb.