I'll curb my enthusiasm for the time being, as experience has taught me, but this sounds like a really neat idea if you can pull it off!
And yeah, Fox, I think you'd almost certainly make a really bad admin, nothing personal, just simple observation based on most of your previous posts.
As for sound effects...
BBC is only for education I believe, and he said he wants to keep this above board, though I don't really know why if it's free, but hey, we've all got our own moral compass. For me, I couldn't care less about using unlicensed sounds if it's a nonprofit project and I'm not using sound libraries from a smaller Indi studio who's artists might actually miss the money, rather than some corporate Goliath who already paid everyone long ago and is now just raking in the royalties.
Anyway, their is a ton of stuff out their with no strings attached if your willing to do a bit of digging for what you want, and I've got some resources for you, I can give you some for music if you want too, just let me know.
The 4 Sonniss GDC Game Audio Bundles (2015 through 2018 so far) have already been mentioned, you'll need quite a bit of hard drive space for them and most of it probably won't be much use in this type of game, but you'll still find a respectable amount of stuff, plus what ever you can repurpose by using your imagination, and it's all high quality.
soundeffectsplus.com, soundgator.com, and soundjay.com all have libraries that overlap, because their owned by the same company, but each site also has it's own sounds.
No I have no idea why they did it that way either, it's annoying, but the quality makes it worth the trouble.
Also we've got zapsplat.com and freesfx.co.uk, the latter of which almost exclusively pulls (legally) from various Sound Ideas commercial libraries, and Sound Ideas are the biggest name in the business, which shows in their quality.
Airbornsound.com is pretty awesome, and he even offers super high quality versions of his free stuff. Plus, if you have a bit of cash, he offers some really cheap bargain bundles too.
Many of the artists listed on sites like asoundeffect and Sonniss also have free sound packs on their own individual websites, (Sound Morph and Soundbits for instance) and you can be sure of the quality, but expect to jump through some hoops to get your loot, basically you'll have to go through full checkout including billing address and all that most times.
Next their is the Adobe Audition Sound Effects Library, which, surprisingly, is actually able to be used outside of Audition and has many great ambience, nice sword sounds, and some good footsteps just off the top of my head, even if much of the rest is either cheesy or overdone.
You've also got PacHD.com and PacDV.com. They both offer sounds, but it's more hit and miss than the ones above.
Moving to the do it your self category you've got sites like freesound.org, soundbible.com, and opengameart.org.
It's a matter of needle in a haystack for these, especially with freesound because the database is massive, but their are allot of gems to be found if your willing and able to put in the time and effort, and same page web player support, sound packs, tags, and author profiles help allot.
Some things, like ambience, are a dime a dozen, and not that hard to find, while other things, like high quality first person perspective firearms, will mean searching through multiple pages to find what you need, but once you've found a solid pack or artist, you can generally get a fair amount of similar material.
Undoubtedly I'm missing some, their is just no real way around it, but I've mentioned all the ones I know the licensing for and used my self, minus those catering to primarily 8bit or heavily synthesized sounds that likely have no place in this game.
The licensing for nearly all of these is either Creative Commons Attribution, Creative Commons no attribution, or a custom license that's pretty common with these sites where you can't use the sounds in something like a sound effects app or sound effects youtube video, e.g. main purpose of the media is to show the sounds unmodified, along with the stipulation that you can't offer the sounds for direct download, or even link to individual files on the sound website's servers.
Aside from that it's generally all the same, but it's worth double checking, particularly when it comes to proper attribution methods, as they can sometimes get pretty picky with that, though more so for music.
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