Crime & Punishment

In that case, I don't see the issue. Anything else would be a suggestion.

Shrinkage is a fact of life for every RL business - 1-2% of sales is considered normal in retail which is about the same as the operating margin for most ventures (so they could almost double their profit if they would manage to eliminate shrinkage).

Just learn to plan with it:

You already did have more restricted access permissions for expensive modules which is good.

Next step would be to control how much of the cheap modules you keep stocked in your public hangars - do you really need all 30 warp disruptors in the public hangar or would 10 suffice when you restock every few days?

Remind people about giving back items they have "borrowed" from public hangars (obviously doesn't apply for consumables such as ammo).

Be a little more selective/cautious in your recruitment process (how come you didn't have API keys with sufficient permissions from the get-go?).

Try a more fine-grained permission management ("director can do everything, everyone else can't do anything" only leads to burnout and frustration) and always consider "how much damage could he inflict?" vs "how much isk/time/effort has he invested so far?" when handing out roles.

Keep your eyes open for early signs of burnout or serious discontent. Try to manage these issues before they become threatening.

Investigate the situation and talk to people before yelling "theft" or making accusations. Maybe some director wanted to re-arrange the hangar layout and had to leave half-way through, maybe your industrial director decided it's time to refine all these useless T1 mods for minerals, maybe someone had to borrow an expensive item for a few hours and forgot to return it...
Try to be neutral in your first reactions - "Where did these items go?" as opposed to "Who stole these items ?!?"
Yelling theft early does not only ruin relations with your corp-mates, it can also turn innocent behavior into actual thefts ("if he thinks I'm a thief then I might as well act like one").

Don't trust anyone. You can give other people access to goods without trusting them not to steal anything.
It's a question of mindset and expectations, not of actions. You sound terribly butthurt and the most likely reason for this is that you honestly thought your corp was populated by trustworthy saints only.

but "lock down everything" is probably the worst possible response to a theft that - in your own words - wasn't even significant isk-wise.

I ran a corp for a few years and we used to maintain a "free stuff" tab in the corp hangar. We used to encourage people to throw stuff in there from rats they looted if they weren't planning on selling/using it.

It was made clear to everyone that "free stuff" meant that there would be no control over what got taken out.

Some people put stuff in, some took stuff out. Every now and then someone took it all and melted it down (I assume). At first this happened on a regular basis, which is unavoidable if you maintain such a hangar, but my attitude was always that if someone needed the isk badly enough to risk stealing it that I would have given it to them anyway.

Later on, we decided to clear out that hangar ourselves because doing nothing about the stuff getting stolen would **** people off. When it started to accumulate we took the stuff out ourselves and melted it down and made ship hulls with the minerals, which we then handed out to people when they did something special or when they lost a ship in PVP. After that the amount of theft dropped and when it did happen I could tell a little white lie (namely that I did it) in order to avoid it affecting morale or starting witch hunts.

T-

In the real world I have noticed there is a minority that will steal anything that is not nailed to the floor, and to be honest, some of that as well. So why wouldn't they steal in EVE. Just tighten things up.. I suggest the CCP leaves it as is, always a place for criminals in a game like this.. not my style of play but EVE would be ever so boring without thieves, pirates, mercenaries, and gankers. Don't like it when they hit me much but I love the feeling of danger here. my opinion.

What I think would make the OP happy is if every single container that could ever be possibly accessed by more than one person, had a accessable "loot history" that would be stored on the CCP server side.

I'm sure he would respond with "wait wait wait, i'm not saying EVERY container in the game, I just want ship maint bays" But you see once you add just one loot log like that, everyone and thier sister wants it for all of them and has a just as convincing and ascinine reason why. Its a slippery slope that can simply be solved by increasing security.