Getting exp 2 asap is almost always a good opening strategy imo…to be changed only if the map forces it (i.e. you need hyper to expand, or start very near multiple aggressors, or you make an ally who is doing exp so you switch to bank/weps/hyper).
The most benefit from terra is given to bad planets (low resources)…so i never worry about that as much early, even in a sparse galaxy – since at first, with so little cash, you should only be spending on your best planets (and they benefit from terra the least).
Also, keep in mind scanning is of greater importance in the dark than it is usually…even in the mid-late game. Scan is likely to allow you to expand further and/or along different avenues, or to fringe (otherwise inaccessible) stars, and also allows you to flank/surprise your opponents (esp when you have higher scan than them). Im not saying its the most important tech, or that you need to do it first or anything…just keep in mind that scanning now is your main access to more information.
I know this sounds obvious, but it can still be easily underestimated or come as a bit of a shock in the game…To play a dark galaxy is to play a game where no single player has all the information about the map…which is the exact opposite of non-dark galaxies. This means you may find some of your skills like determining alliances (yours and others), grand strategy, and diplomacy are hindered because you no longer have access to all the knowledge that seeing the whole map affords. It can be hard to convince someone to your preferred way of thinking when you cant even see them or their map position. The more scan you have, the more the game starts to finally feel and play a bit more like non-dark.