I think total conversion should also have its own category (I assume these are not mutually exclusive), so people would know what mods remove the base factions from those that do not.

Well, did you have mutually exclusive or non-mutually exclusive categories in mind? If they are mutually exclusive, then Myfist's categories do not make sense as many mods do all those things. If they are not, then total conversion should be another category alongside "New Planets", "New Ships", "New Music" etc.

Ah, my mistake. A Total Conversion is indeed a mod that tries to make an entirely different game out of the Sins engine. Of course few actually get to that point so my definition is any mod that removes the original Sins factions. Sins of a Galactic Empire, Sacrafice of Angels, and most of the other Sci-fi show/movie inspired games fall in this category.

Mods like my Enhanced 4X mod or Infinite Space I label as "Enhancement Mods", they may add a lot of new content but usually they do not usually add new races. Some like Infinite Space focus on just one theme, in that case "Planets". Others like Enhanced 4X and Distant Stars systematically change virtually all aspects of the game to some degree, and often package some of the specific themed mods into them.

Mods like Maelstrom and Requiem fall into a interesting category in that they add new races but do not remove the Sins ones, and in ZombieRus' Sins of a Fallen series is interesting as you pick and choose which races you want to play with from a set which includes both new and default ones. Still, I think these belong in the Enhancement category, perhaps with a "Adds New Races" category as well.

Well quite honestly, even if all the mods on Moddb and the forums here got but on your site, some categories will still only have a few files in them. But the broadest you can get would be "Total Conversion" and "Enhancement". To be a bit more specific, "Total Conversion", "Planets", "Races", "Units", and "Sound" would be the most useful categories to start with IMO.

Well I plan on having it have mods and mod resources.  Or simply put, all files that are useful to soase players/modders.

I won't allow my mod to be posted here... no offense or anything. I bet most other mods beyond simple one offs would want their work here either.

I made it as simple as possible in my review thread. 

Original factions removed := Total Conversion

Adds new factions and keeps original := Expansion Mod

I'm talking about the mod files itself as a file sharing device. If you have something similar to Rick's galaxy that has links to where the mod may be downloaded, then that's fine.

I think overall the ideas are fine for this project, but don't expect everyone to leave moddb or their own hosting sites to jump on board with their projects.

A long time ago I made a "Directory of Planet Mods"...I was kind of busy at the time so I didn't really try to do a whole lot with it other than sort of organize a variety of planet mods...

For each mod, I posted a link to the most relevant thread on the sins forums...I started with having actual links to my own mediafire account where I had back up copies of several mods...however, I asked each modder (if they were still around) for explicit permission before actually hosting their files...some were a little slow at responding so I kind of did the "do it now, ask for forgiveness later" approach, but I immediately removed any links to my own hosted downloads as soon as the mod owner requested it to be taken down..

I clearly stated my intention of my downloads as being backups in case for whatever reason the modder's own links or website fell out of use...this was at a time when some people were transitioning from Trinity to Rebellion so there was a very real fear that some graphics mods might become completely abandoned...in any case, people still treated my links as "live and up-to-date" and in the end it became clear that hosting copies of mods just wasn't a very good idea...

Moral of the story....link to threads or websites, DO NOT host direct downloads...now, you may want to keep a personal cache of downloads and if you see one fall out of existence, well then it might as well be "public domain" for all intents and purposes...

It sucks, but it saves me from writing all the web code myself (though I have a crude mod website ready to deploy if I should ever need it). Also the larger user base is also a plus. Can reach people who wouldn't normally keep up with Sins mods that way.

Guys, linking to wherever you want it to link to is more than fine with me.  In fact, it's better because it keeps my bandwidth down on the site!  I can create the links myself, but I would prefer that the authors do that.  This is because there is also an update tab where you can put a change-log, but it's up to you.  I'm just trying to help with the mod components people would like in a central place and a master link list to the mods available, like Seleuceia referenced.