This is one plan for efficiently using a small number of Tiles to get a core of strong, productive Bases for your Faction in basic SMAC.

Each Base will only ever need an additional 5 Tiles to work, so you can place your Bases close together for better defense. Have your Terraformers plant at least 5 Forests for each Base to start. If each Base has Recycling Tanks and a Recreation Commons, then you can have three Workers in as many Forest Tiles (1 Nutrient, 2 Minerals, 1 Energy) along with the Base itself (3N/2M/2E) for (6N/8M/5E) total production per Base. You can eventually use Supply Crawlers for the other two Forests to bring in an additional 4M per Base (6N/12M/5E). Rocky Tiles with Mines and Roads would be even better. If you temporarily set some of the Crawlers to bring Minerals to your HQ, then you should get enough Ecological Damage (ED) to cause a Fungus Bloom. Each Bloom causes an increase in the amount of Minerals your Bases can use.

Depending on your Faction's overall Efficiency, you can initially grow your "Great Forest" to about 6-8 Bases without extra drones. Have each Base build a Tree Farm (which also increases the amount of minerals you can produce per base before additional ED) and a Children's Creche. Once you discover the necessary techs, have your Formers convert the Base's five Forest Tiles, two to Boreholes and the other three to Farms. Two of these Farms should also have Condensers. I usually put a Road and a Sensor Array in the Farm without a Condenser. Use Crawlers to collect the Nutrients in the 3 Farm Tiles. Two Workers can collect both Minerals and Energy from the Boreholes. That gives you enough Nutrients for the 2 Workers plus 5 Specialists. The Bases should ideally have a basic "6-pack" configuration:

(Farm+Condenser)-(Farm+Array)-(Farm+Condenser)
(Borehole+Worker)-(Base Tile)-(Borehole+Worker)

So that is:
-two Boreholes with Workers (0N/12M/12E)
-two Farm+Condensers with Crawlers (8N/0M/0E)
-one Farm with a Crawler (3N/0M/0E) If this farm is located between the two with Condensers, then it will have 3N.
-the Base itself (3N/2M/2E)
-five specialists of your choice (EC/Labs/Psych)
Total: (14N/14M/14E) plus Specialists' income

FYI, Democracy with Planned plus the Children's Creche (DEM/PLAN+CC) will give your bases enough Growth to boom up to the max population of 7.

Since you mostly have Specialists in your Bases, you can have as many as you can build. If the two workers ever go Drone, then just add enough Psych from Specialists to correct this. Let's say that you eventually have 14 of these bases up and running. That might be two columns of 7 bases (each column of 3 Tiles across and 14 in length) with a column of 14 single Tiles between them to keep the Boreholes from being adjacent. That's less than 100 Tiles to defend.

Finally, when you get the Spaceflight techs you can have each Base build an Aerospace Complex, and a Sky Hydroponics, Orbital Power and Nessus Mining satellite. These give each size 7 Base an initial +7 N, M and E boost. Build a Hab Complex in each Base and as the size of the Base increases to 14, so does the boost from the satellites. Again with (DEM/PLAN+CC) the population booms up to the new max. Each "6-pack" had a basic production of (14N/14M/14E). The satellites eventually add (14N/14M/14E), doubling each Base's production to, you guessed it...(28N/28M/28E). That's better than (4N/4M/4E) for each tile in every one of your Faction's Bases!

As to the 14 single tiles between the columns with bases, add 3 or 4 more bases with only four squares each. That would be one for the base itself and three with a crawler on a farm+condenser (or two with farm+soil enricher+condenser). You can boom this up to seven population. With an aerospace complex it will continue to grow to 14 pop and get minerals and energy from the satellites.

Of course, Boreholes can't be built on slopes, so the ideal 6-Pack arrangement is not always possible. I usually find about one Rocky Tile per Base, which can be mined with a road for an additional 4M with a Crawler. Even with this, your actual territory for your Faction can be around 100 Tiles and still have 250 population and plenty of Minerals, Energy, Economy, Labs and Psych. Good luck!

Yeah, this is a valid strategy. ICS is generally good in SMAC. There are some extreme variations, where you build basically just the colony pods for much of the game. Also a tighter empire is easier to defend.

Economy-wise you have a choice between larger cities with tree farms or a few mega cities working off of collector fields.

Thanks! The best part of this strategy is that it counters all AI strategies. You have a large population to thwart a diplomatic or cooperative victory., You produce lots of energy credits to stop an economic victory and you occupy a strong defensive position to hold off the AI until you Transcend.