I can indeed tell you a different story:
Previously, colonies were worth it only if you had a combination of good administrators and AI cores to stuff them with, in addition to the constant early colony babysitting.
0.95a has introduced a lot of changes to colonies, most important of wich being "colony artifacts" that can be installed on specific colony structures if they meet the requirements. These can range from improving various aspects of a colony to giving massive boosts to production.
This change, along with a nerf to the speed at wich pirates and the like start pestering your colony, has made founding your first colony a lot easier. Also remember to always keep the Hazard pay on.
You did the best thing by colonizing a terran planet first, since you can easily turn an early profit with just mining and farming. I personally look for my first two planets with the following charachteristics:
1)they must be in the same system
2)the first planet I colonize must have very good farming (good farmland and/or Orbital Solar Arrays massively boosting it), very good mining (both ore and rare ore plus organics).
3)the second planet I colonize must have no atmosphere and a not too high hazard rating. Bonus points if it has low gravity
I tend to build ALL my planets with structures in the following order:
1)first industry and upgrading spaceport into megaport as soon as the spaceport is built
2)space station, patrol HQ, ground defences,way station (in this order)
3)Second industry slot as soon as it is available
4)upgrade ground defences into heavy batteries and station into battlestation
5)Third industry slot as soon as it is available
6)Upgrade battlestation into star fortress
7)Fourth industry slot as soon as it is available
My first planet more or less never upgrades the patrol HQ, I dedicate all four slots into economy, namely agriculture, mining, commerce and light industry. This planet will not attract inspections because there is no AIs, it will not attract pathers because it will have no heavy industries and fuel production and it will have no pirate activity ruining it's economic if you are NOT hostile with the Pirates, wich I suggest you work towards. It will generate between 150k and 250k a month once it reaches size 6 without any AI provided you got a colony artifact or two roiding some of your industries up.
My second planet will be dedicated to heavy industries, fuel production, force projection and a decent income once it gets popolous. I instructed you before to choose a planet with no atmosphere because of this: Heavy Industries using either a corrupted or pristine nanoforge will add the pollution trait to your planet if it has an atmosphere, wich raises your hazard rating. A Syncotron core for your fuel production will also not be able to be installed if the planet has atmosphere. Opting for a planet with the "Extreme heat" as a colony condition might sound counterproductive but it actually is not. There's a colony artifact called Cryoarithmetic engine wich boosts colony fleet size by 100% if it is installed on a planet with Extreme heat, wich will basically make all the colonies in the system invulnerable to raids.
You can more or less do anything you want after that. You can feasibly colonize every single bloody planet in the system and be assured that every single one of them will eventually generate decent income one day. Diversifying the industries and processing facilities of all planets in the system will also make sure you can supply most of the needs in-faction, drastically reducing income loss die to hostilities with other faction and almost completely negating the "incoming shipment lost" debuffs.
You do not even have to strictly colonize only one system. I've currently got 4 colonized planets in 3 different systems generating around 500k a month and this is WITH -65% to accessibility due to hostilities with other factions AND the fact I may have raided too much causing the degradation of a couple dozen planets.
I hope you got to the end of this unending rambling. Thank you if you did and I'm going to be happy if it actually proved to be useful!