I just started Chapter 17, and am Marble/Crystal/Gem boost, and so shall walk through some numbers from my then point of view... Substitute your numbers to my computations for a better evaluation for your circumstances.
Base
Lvl 31 Marble, 25 squares, 750 Marble/3h, 250 Marble/h, 10.00 Marble/sq/h
Lvl 31 Crystal, 28 squares, 745 Crystal/3h, 248.3 Crystal/h, 8.87 Crystal/sq/h
Lvl 31 Gems, 30 squares, 920 Gems/3h, 306.7 Gems/h, 10.22 Gems/sq/h
700% Relic Boost
+70 Marble/sq/h, Total 80.00 Marble/sq/h
+62.09 Crystal/sq/h, Total 70.96 Crystal/sq/h
+71.54 Gems/sq/h, Total 81.76 Gems/sq/h
Supplies
Lvl 39 Workshop, 30 squares, 43,400 Sup/3h, 14,467 Sup/h, 482.22 Sup/sq/h
Lvl 31 Marble, 1,500 Sup/3h, 500 Sup/h, 20.00 Sup/Marble Sq/h, 0.041 Workshop sq/Marble sq/h
Lvl 31 Crystal, 6,880 Sup/3h, 2,293 Sup/h, 81.90 Sup/Crystal Sq/h, 0.170 Workshop sq/Crystal sq/h
Lvl 31 Gems, 27,200 Sup/3h, 9,067 Sup/h, 302.22 Sup/Gems Sq/h, 0.627 Workshop sq/Gems sq/h
Population
Lvl 39 Residence, 20 sq, 9200 Pop, 460 Pop/sq
Lvl 39 Workshop, 12,379 Pop, 412.63 Pop/sq, 0.90 Residence sq/Workshop sq
Lvl 31 Marble, 15,246 Pop, 609.84 Pop/Crystal sq, 1.33 Residence sq/Marble sq
Lvl 31 Crystal, 21,302 Pop, 760.79 Pop/Crystal sq, 1.65 Residence sq/Crystal sq
Lvl 31 Gems, 27,758 Pop, 925.27 Pop/Gems sq, 2.01 Residence sq/Gems sq
Roads
Lvl 39 Residence, 1/2 * 4 squares = 2 squares, 0.100 Dune sq/Residence sq
Lvl 39 Workshop, 1/2 * 5 squares = 2.5 squares, 0.083 Dune sq/Workshop sq
Lvl 31 Marble, 1/2 * 5 squares = 2.5 squares, 0.100 Dune sq/Marble sq
Lvl 31 Crystal, 1/2*4 squares = 2 squares, 0.071 Dune sq/Crystal sq
Lvl 31 Gems, 1/2 * 5 squares = 2.5 squares, 0.083 Dune sq/Gems sq
Culture
Dune St, 1 square, 430 Culture/sq
Ch17 Lava Codex, 4 squares, 7,500 Cult, 1,875 Culture/Codex sq
Lvl 39 Residence, 5,524 Cult, 276.2 Cult/sq, 0.1473 Codex sq/Residence sq
Lvl 39 Workshop, 8,701 Cult, 290 Cult/sq, 0.1547 Codex sq/Workshop sq
Lvl 31 Marble, 4,415 Cult, 176.6 Cult/Marble sq, 0.94 Codex sq/Marble sq
Lvl 31 Crystal, 11,333 Cult, 404.75 Cult/Crystal sq, 0.22 Codex sq/Crystal sq
Lvl 31 Gems, 9,690 Cult, 3,223 Cult/Gems sq, 0.17 Codex sq/Gems sq
Combined
Lvl 31 Marble sq
Produces 80.00 Marble/sq/h
Supplies requires and 0.041 Workshop sq
Population requires 1.33 + 0.041*0.90 = 1.37 Residence sq
Roads requires 0.1 + 1.37*0.1 + 0.041*0.071 squares of roads = 0.240 Dune Street
Culture requires 176.6 + 1.37*276.2 + 0.041*290 - 0.240*430= 670.084 Cult/sq, .357 Codex sq / Marble sq
Total sq = 1 + 1.37 + 0.041 + 0.240 + 0.357 = 3.008 squares
Overall 80 Marble/h using 3.008 squares, or 26.60 Marble/h/required sq
Lvl 31 Crystal sq
Produces 70.96 Crystal/sq/h
Supplies requires and 0.170 Workshop sq
Population requires 1.65 + 0.170* 0.90 = 1.80 Residence sq
Roads requires 0.1 + 1.80*0.1 + 0.170*0.071 squares of roads = 0.292 Dune Street
Culture requires 404.75 + 1.80*276.2 + 0.170*290 - 0.292*430= 825.65 Cult/sq, .440 Codex sq / MarbleCrystal sq
Total sq = 1 + 1.80 + 0.170 + 0.292 + 0.440 = 3.702 squares
Overall 70.96 Crystal/h using 3.702 squares, or 19.17 Crystal/h/required sq
Lvl 31 Gems sq
Produces 81.76 Crystal/sq/h
Supplies requires and 0.627 Workshop sq
Population requires 2.01 + 0.627*0.90 = 2.57 Residence sq
Roads requires 0.1 + 2.57*0.1 + 0.627*0.071 squares of roads = 0.402 Dune Street
Culture requires 3,223 + 2.57*276.2 + 0.627*290 - 0.402*430= 3,942 Cult/sq, 2.102 Codex sq / MarbleGems sq
Total sq = 1 + 2.57 + 0.627 + 0.402 + 2.102 = 6.701 squares
Overall 81.76 Crystal/h using 6.701 squares, or 12.20 Gems/h/required sq
I'll put up comparison Traveling Merchant numbers shortly
Edit: Corrected some Copy-and-Paste errors