Thanks for coming out to chat with is Iain, I can tell you the exact reasons why I resisted buying from your store and the reasons I am resisting buying the game.
First the store. If I went ahead and bought Pandora, at the very least I would have to enter in all of my billing and credit card info, none of which I have to do when buying from Steam (because I have already done it). I would also have to provide an email address. As a general rule, that means getting an email from that service/company/whatever once a week to once a month, a lot more for some services. I could provide a fake one, but then it would be hard to find my game, which brings me to my next issue.
If I get a game from a new service there is a good chance that I will completely forget everything about the game a month after I stop playing it. A good example is a came called Starscape. I bought it for $10 from their webpage probably 10 years ago. Played it for a long time and enjoyed it. Then I stopped playing it. I couldn't even remember what the game was called, let alone who made it, or my user name and password, or anything like that. It is just too hard to have more than a couple major game providers.
There is also the issue that I don't know much of anything about your service. I haven't seen good or bad reviews of it (I haven't looked, to be fair). If I really wanted to go after Pandora, honestly, I start a thread here asking people's impression of the service. Also, since it isn't a major name, I am slightly apprehensive to give out my credit card, even though I have a very low limit one specifically for unknown vendors. I don't even know if I have to download a front end to download from you or if games update automatically.
About the game:
Sounds great. I seriously loved Alpha Centauri and I would love a game that captured the passion I felt for SMAC years ago. A modern day remake gets me excited. On the other hand, I also loved Master of Orion 2, but all the modern day remakes fell seriously short, for one reason or another. Games like this are so deep you really have to research the mechanics of the game to decide if you will like it. There are a lot of things developers can "do wrong" in my opinion. It makes it extremely difficult to say "I will enjoy this game enough to justify my purchase."
In the end, I'd look past all of these issues and pick the game up if it was $10. I am willing to risk 10 or 15 dollars on an unproven developer or service. I can make up that money by cutting out Starbucks for a week. But $30? I could pick up a bunch of old Strategy games I used to enjoy for that much and see if they are still worth it.
Long and off topic post, so, sorry for that but I think Iain deserved an explanation.
Now you more adventurous dwarves tell me how the game is.