Interesting thread. I think there needs to be two teams, one for any NZ non-test players, and another excluding players who played before 1930, when NZ played their 1st test.
For the all players team, the list in 1st post is good start, but I would add Greg Hay (best non-test opener across the last 7 seasons), Syd Smith and Bert Kortlang (eligibility controversy!), a better keeper, and a 2nd specialist seamer.
Smith had a long career in WI then England, but played 9 successful seasons in NZ (1890 runs @ 39, 149 runs @ 22) and was selected for NZ teams from 20-21 to 23-24, so I am picking him here.
Kortlang is Australian, pre WW1 had 19 games 1395 runs @ 49, then moved to Wellington aged 42 and had 4 good FC seasons (1293 runs @ 49.73, 4 x 100s). He was picked for a NZ team in 1923-24 so I am picking him here.
Nevin could bat but I want a specialist keeper, as there is enough batting depth with all-rounders Smith, Reese and Alabaster. Three obvious options are Dick Rowntree (Auckland, 1st choice NZ keeper into his 40s), George Mills (Otago, unlucky not to be picked to 1949 Eng tour) and Len Kent (Auckland, amazing stumpings stats, 49c 32s in career).
My team has 3 specialist seamers (2 in the starting XI). Pritchard is an obvious choice (pre war in NZ 89 wickets @ 16.78), and the stamina of Stan Brice wins him the spot as his opening partner. The 3rd seamer would come into the playing XI on a green pitch. Options are Dan McBeath (Cant + Otago, LFM swing), Cyril Parsloe (Wgtn, added to NZ team in Aust at end of 1937 Eng tour, 69 wickets @ 22), Don Clarke (Auck and ND when not playing for All Blacks, 117 wickets @ 21.14), Bob Sutton (Auck opening LFM, 156 wickets @ 22.41), Andrew Penn (252 wickets @ 23.03) and Adam Milne (FC record 88 wickets @ 32.63 not great, but has extra pace to make him useful at "test" level).
So XII is:
Lancelot Hemus, 2916 @ 36.00, 8 cent.
Greg Hay, 5569 runs @ 43.17, 13 cent.
Syd Smith, 10920 runs @ 31.28, 14 cent, 955 wkts @ 18.08
Syd Hiddleston, 3818 @ 39.77, 8 cent. 86 wts @ 26.88
Bert Kortlang, 2688 @ 49.77, 6 cent.
Ces Dacre, 12223 @ 29.17, 24 cent.
Dan Reese (c), 3182 @ 25.25, 4 cent, 196 wkts @ 19.86
Gren Alabaster, 3200 @ 23.88, 3 cent, 275 wkts @ 23.22
George Mills, 2056 runs @ 19.96, 2 cent, 88c 34s
Stan Brice, 1575 runs @ 17.11, 247 wickets @ 21.29
Tom Pritchard, 818 wkts @ 23.30
12th man
Dan McBeath, 170 wickets @ 20.83
Post 1930 team needs more thought.