In my opinion, your colonies are solid planets with great potential in making loads'a'money. They're a bit low on the resource deposit side, but prime real estate in the sector is a rarity. Here are some ways to improve them:
1) Find some colony items! They dramatically boost your production, given the correct planet type and conditions. Most colony items can only be found by exploring the galaxy at large, so it's random. Look for Research Stations, Mining Stations, Survey Ships, and Motherships. Finding them and figuring out how to use them is part of the fun!
--1a) A recent update made it so that the Mothership has a guaranteed drop for 1 of 3 possible Colony Items. Two motherships will spawn per galaxy.
--1b) Neutron Stars, Blackholes, and in my experience, plenty of Gas Giants in Nebula systems have a high chance of having Research stations.
--1c) Most factions have a few colony items installed on their worlds... and you can steal them with Marines in a raid! But it's usually pretty hard. Blow up the station, find ways to reduce stability, or do a targeted bombardment to soften the ground defenses up.
2) The key to high income is a high population (they increase all production + more slots for money making industries) and accessibility. Accessibility is important for aforementioned pop growth, as well as determining market share %. When there's a comm relay in the system, and you're on a colony screen, you can click on the commodities on the side to open up the market. There, you can see how valuable each good is and how much your faction is raking in. Long story short, the more accessible you are, the easier it is for the goods to reach the Core consumers!
3) Your industries demand certain commodities for production. If your faction at large can produce these commodities, you will be rewarded with up to a -50% Industry upkeep discount. Since most of your colonies have average/high hazard rating, that is putting a big dent on your profit. The discount will help tremendously.
4) Do your administrators have any special skills? The ones that do are much more expensive in salary, so I advise employing him on your high population colonies with lots of industries. Then, his skills will outweigh his cost!
5) Installing AI cores. Do not spam install Gamma cores, there's some complex market math that can end up making you less money. But nullifying a commodity shortage you can't seem to fix is 100% worth it. Beta cores provide a -25% industry upkeep discount, so they're great. Last but not least, Alpha Cores are very rare, very profitable, and very dangerous. However, there's minimal penalty to installing them directly in an industry of your choice to supercharge. Try slotting one in the Commerce on your Tundra world!
6) Lastly, maintain minimum 5 stability on all of your worlds. Like other posters have mentioned, every point of stability below 5 incurs a -20% total colony income per difference. High stability is good for defense purposes, so come back to that later when you inevitably drown in infinite cash!
Go forth, and employ these moolah principles. Come back again if you have questions, I left you lots of room to do exploring on your own!
