I would qualify rep-building as part of the single player game experience-as I would the whole concept of a freelancer. Its almost a contradiction...how can you have a freelancer when there are no real player factions? Instead of players acting as the factions in the mod would, disco has gangs of freelancers wearing faction colors, then doing whatever they want. To me, the definition of being in a faction is sort of like marriage: easy to get into, costly to get out of. Only in multiplayer versions of freelancer you can change factions like you change your socks. The ease with which we change our faction hats means that none of the player-characters ever really become part of a faction. We never 'marry' into it-become commited (some try valiantly to impose these limitations by choice, but are always forced to interact with others who choose not to-then start making exceptions to their own rules.) If you aren't commited out of necesity to a faction's way of life, its limitations, it's strengths then you aren't doing justice to it's niche in the Sirius system.
I like the idea of keeping some freedom in the game. Mods like excelcia are perhaps too limiting. Perhaps this discussion should be one about faction-making rules, rather than mod development? Maybe there should be tighter rules on how player factions behave and more community revue of faction concepts. At the same time one could leave individual/true freelancers alone to do as they please. Freelancers would be true freelancers-tagless, and whatever rep they choose. It would at least approach the best of both worlds without adding the mess of something like a nexus-system.