I haven't written a developer journal in ages, but with the release of the Stellar Phenomena DLC for Sins of a Solar Empire: Rebellion today, I thought I'd give it a go. This DLC adds a number of elements to Sins that I've long thought of, so seeing it come into being has been a blast. As with everything Sins, I worked closely with Ironclad in designing Stellar Phenomena, as did the rest of the team in creating it. I love getting to work with Ironclad on this stuff, so the past couple months have been pretty sweet. 
When we made Forbidden Worlds, our goals were pretty simple: we wanted to add a little more specialization to planets, increase the types of planets in the game, and add in some more planet bonuses. Revising the planet textures during this process was a bonus, as was being able to more than double the number of planet bonuses available as a way to flesh out the Sins universe. Did you know that if you select a planet with a bonus and then hover your mouse over the slot in the lower left center of the UI that an Infocard will give you lore info on it? Honestly, I didn't for a long time, but there's some cool stuff in there!
After the success of Forbidden Worlds, we started to think a lot on what we could do next in the Sins universe and we went back and forth brainstorming with Ironclad. As many Sins players know, we're very limited in what will safely 'fit' into what's left of our 32-bit (2 GB) memory limit, plus what will overtax the simulation and what we can actually accomplish with the time we have. It's actually the #1 consideration we face right next to making sure we stay true to the Sins universe.
One thing that we've always felt Sins needed more of were special, non-habitable gravity wells that had some kind of strategic significance on gameplay. To address this, we went in two directions by adding three new types of stars (Black Hole, Pulsar, and Neutron Star) and six new types of gravity well in the DLC (Comet, Antimatter Fountain, Radiation Storm, Ship Graveyard, Shattered Dwarf, and Ice Field). Each of these new areas has some kind of effect on passing vessels, or in the case of the Ship Graveyard, is a resource rich area to hold via its special outpost.
Another new feature we added in the DLC was random events. This is a feature that we've talked about for years as a way to force players to deal with situations they couldn't entirely foresee. Of course, since these events are potentially very...shall we say...disruptive, we've made this a gameplay option (enabled by default). Some of the events you may encounter are quite beneficial like the Economic Upturn that gives all players a big boost to income and trade; however, others may bite you if you're not careful. One of my favorites is Partisans, so you'd better watch out if you're going to lose a planet to culture! Not all events are global or stationary either - some may move around the map, forcing you to re-evaluate your strategies.
I and everyone at Stardock and Ironclad hope you enjoy Stellar Phenomena!