There is something I find interesting:
I counted the missions act both in FreeSpace 1 and 2. The result was quite strange: the campaigns of both games consist of 29 main missions(Training, and SoC not included in this 29). Regardless both has the same mission number, FS2 appears to be FAR longer than FS1. I find this interesting because I can complete the Great War over a day if I have mood to do that, but FS2 can take three or four days to me.
I don't know why I write this down here, but that is one of many things I find interesing in the world of FreeSpace.