Some more stats (bearing in mind I'm bound to have made some errors...):
Top scorers in the group stages:
406: Everton Weekes (1x100, 3x50)
384: Norman O'Neill (2x100, 1x50)
358: Phil Mead (4x50)
343: Wally Hammond (1x100, 1x50)
340: Len Hutton (3x50)
10 centuries so far, the highest being 132 by Hammond and 130* by Weekes.
Top strike rates (100+ runs)
131.40: Jim Parks (113 @ 56.50)
109.80: Polly Umrigar (168 @ 28.00)
108.47: Norman O'Neill (384 @ 64.00)
106.80: Cyril Washbrook (110 @ 18.33)
103.05: Everton Weekes (406 @ 81.20)
Mead and Hammond also have a strike rate of >100.
18: Allan Steel
17: Subhash Gupte, Johnny Wardle
15: Ranji Hordern, Fred Trueman, Neil Adcock, Wilfred Rhodes
10 5-fors, including 6-30 by Gupte and 6-46 by WG Grace.
Most economical bowlers (100+ balls bowled)
3.39: Trevor Bailey (14 @ 11.14)
3.73: Mike Procter (13 @ 15.77)
4.04: Fred Martin (8 @ 22.75)
4.06: Fred Spofforth (10 @ 19.00)
4.12: Wes Hall (9 @ 23.78)
Allan Steel (6.96) has the second worst rate, only beating Sonny Ramadhin (6.98).
A possible "best of the group stages XI":
Norman O'Neill
Len Hutton
Phil Mead
Everton Weekes
Wally Hammond
Jim Parks+
Jack Gregory (203 @ 67.67, sr 100.50; 10 @ 23.60 ec 4.37)
Trevor Bailey
Mike Procter
Fred Spofforth
Subhash Gupte
Bailey and Procter are batting so low because they're in as bowlers - neither has scored many (or quickly).