In earliest part of game, always at least 1 forest on flat terrain per base, to increase minerals output of terrain. Similarly, settle the base on flat terrain. Don't waste rolling terrain with that, you're going to want farms there soon. When a base lacks a resource special, you will often see 1-1-0 tiles being worked, or even 1-0-0 if you've got piss poor land. It is a slam dunk obvious optimization, that it is better to get 1-2-1 from some tile, than 1-1-0. In the very beginning, you are also often managing your people's happiness. You do NOT necessarily want to have your population explode, without providing you productive capacity. A forest does that. Also when that base gets to size 2, you want it to cough out a colony pod quickly, at the beginning. So that may be 2 forests or 1 forest and 1 farm. NOT 2 farms. Your people will get fat, you will not have much minerals for doing things you want, they will riot.
If you have the good luck of settling on a flat tile with a nutrient special, you can support LOTS of forests. Like 3 maybe. The minerals yielded, are as good as having a high quality mine. You can get early secret projects done this way. Or build good trained troops from 1 Command Center.
Because I plant these forests at the beginning to get the minerals, they tend to spread. They will cover up good farmland squares. That's ok: you will get 5 minerals added to your production when you rip the sucker up to make farmland.
Lately I am heavily into The Weather Paradigm on 256x128 maps. I make heavy use of Condensers, and will also do a land bridge to connect a starting island to a larger continent. Condensers go on rolling, arid terrain, that is adjacent to yet more rolling, arid terrain. Or at least not rainy terrain. This gives nice farmland with minerals.
Putting the Condenser on a river is nice because otherwise you can't get energy from a Condenser square. Later on, when I have spare Former capacity, I will Drill to Aquifer on Condensers and rocky mines. Those are places lacking energy and the river gives some. I drill right on top of the Condenser or mine because I'm not really sure I can aim the river to run where I'd like it to go. Doing it right on top of target is a sure thing. For more rivers, start them simultaneously. Once you have made a river, you can't drill another river anywhere adjacent to it. If you think this is weird or a cheat, just call it your Everglades terraforming project.
I build solar collectors on my farms, always, unless there are certain resource specials. I always farm rolling terrain. If it's flat terrain, I'll try to do something else with it. Planting forests makes sense for flat, moist terrain. If it's flat and rainy, well maybe I will farm it eventually but never at the beginning.
I will raise land near my bases, to "fish" for resource specials. Quite often they appear, blocking you from doing any further expansion that way, if you want to keep the special. Which I do. I don't like destroying valuable stuff. If you can't figure out how to make use of those things with a base, you can send out sea supply crawlers to suck up the benefits.
Earlier in the game, raising land near your bases to maximize your land footprint, and minimize your "seaport" squares, can be a good idea. Land generally yields more productive benefits earlier in the game. The tile manager that you click on is also pretty stupid about sea tiles, and I don't like manually micromanaging a city's tile choices.
I have experimented with raising land energy squares to 3000 m, but this tends to destroy coastal resources, so I don't do it much. I'd change my tune if I found those land energy squares in the interior of a big continent.
Trying to raise land to increase rainfall, is risky. It tends to change lots of things around, making other areas worse off. The behavior of Condensers is much more reliable IMO. Also faster, and doesn't cost you money.
