rows that accommodate two res units work well. i.e. 2x11.
I just packed mine tight and left the other 1/2 of the map for my endgame. That way I can drop new roads and shuffle the buildings over for the endgame layout, then backfill as desired.
I saw a similar layout to mine that I'l write out below - this layout gets you 1.1 mil on barely 1/2 the map.
note: on left there is a 3 wide space plus a vertical road, on right a vertical road road too. The left side is lined with water, recycling, high School, civic buildings, and other 3 space wide buildings.
legend
SS=solar, F=medium fire, FR=large fire, PO=large police, P=medium police,
G=gamble (the max one), HO=hospital, UNIV=university, P=two parks, p=single park,
B=building, T=transport (helipad), M=Washington Monument, L=library
SSFSSHOFPSSf
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BBBBBBBBBBB
BPBBBPBBBpB
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BPBBBPBBBpB College
BBBGTBBBBpB
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BBUNPOUNBpB School
BB IV FR IV BpB
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BPBGTPBBBpB
BPBBBPBBBpB HQ building
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BBBBHOBBBpB Sydney
BBBGTBBBBpB Opera
============= House
BPBBBPBBBpB
BPBMTPBBBpB
=============
BBUNPOUNBpB
BB IV FR IV BpB Ferris
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BBBTGBBBBpB
BPBBBPBBBpB
=============
BPBBBPBBBpB
BBBBBGBBBpB
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