Great thread, and great idea.
Ive played through SF1 and SF2, as well as Starcontrol series...
Things that Star Flight did that were awesome:
-Vast planets that you would need you to land to explore, you couldnt tell everything about them from space;
-Some real dangers (Uh-Lek fleet would tear even the max upgraded ship to shreds on SF1);
-A sense of existing background lore, although not just thrown at your face, a big deal you needed to uncover by putting things together yourself;
-You needed to work for information, and just aquiring new information was very rewarding on itself;
-Characters that could become better at their jobs;
-Some things were there and just left you with a question, and no answer, or a very vague idea of what was going on. Like the probe, the minstrels, and the encounter with what I would guess to be the Enterprise. Or even the planet at the lower right corner of the map, apparently a colony of the ancients, full of enduriun;
-Secrecy and clues. This is something I miss too much. And without it, I believe no matter how big you make the universe, if you are always sure of where to look for and when, it will not feel as big. I feel such with games like Fallout 3, that have a huge potential for exploration and discovery, but since you always know beforehand what you will find (and even more, just knowing you will find kills the mood), the huge amount of content becomes kinda pointless, the big world only annoys you with long travel distances;
-No handholding. This is something I like on both SF and SC2. More on SF, but SC2 still kept it interesting enough. In SF1 if you did not made an effort to discover and interfere with what was going on, you could run out of time without having the slightest clue of why did the sun flare (and in fact I did so on my first play). And I felt this contributed a lot to the feeling of "openess" the game had. The story was linear, simple, not even sidequests. But simply being able to do things in whatever way you figured out without the game telling you "dude now go there and do this", felt great.
-The spemin were awesome.
Things that were not really so good:
-The mechanics of mineral harvesting, which was pretty much the only way to build resources early on, were really slow. I like the idea of searching for minerals and picking them up, and I reccon its a very good way for an early game strategy. But there should be other means to aquire resources, in special life forms, artifacts, trading, even doing side quests or picking up jobs around, I dont know. Just not spending over 10 hours harvesting minerals would be awesome ;
-Conversation with aliens, although was quite interesting, could be a little boring at times. SC2 was much better in this regard. Although I feel SC2 miss the diplomatic options;
-Battle was very monotone (over power or death);
-Ship upgrades were very straight forward and one dimensional (although the armour levels having an impact on speed was great in my opinion);
-Although the crew could be trained, they developed into full potential way too soon to have any impact on the game, and you didnt have much oportunities to grow attached to them. You would only remember them when they would screw up on their jobs (which after a while simply would not happen), or when dead on the terrain vehicle ;
-The crew was absolutely appathic to anything that happened on the universe. Finding Earth? Who cares, no comment whatsoever. Saving the Universe, been there, done that...
-The Gazurtoid could have more conversations, even if hostile.