I actually have one suggestion to add to the existing implementation, one that will help greatly to combat the living on whoinvis greatly, but also not punishes those who legitimately use it to carry out covert actions that may need it. Namely, could we tie the price of purchase whoinvis to whoinvis/online ratio?
So let's say that you were online last week for 20 hours.
If out of those 20 hours you spend 15 on whoinvis, then purchasing whoinvis again will cost you say 4-5k exp. And if it's 20/20 heck, make it 7-10k even, as it was stated repeatedly that this is not the desired state.
Buf if out of those 20 hours you only spent like, dunno, 6 on whoinvis, then the price will be at 1k. And if it's under that number, it can go as low as to 200 exp for purchase.
Numbers really took out of my rear end so no need to nitpick as they are most likely wrong, but I think this would be a sound idea. People who use whoinvis sporadically but do leave themselves "vulnerable" (just by being online, no need for actual RP) will be able to keep purchasing it cheaply. And those who live on it permanently will pay a severe price for it.
This wouldn't take away the current system of earning it at all, just make it harder to play on alts to sustain perma whoinvis. Becuase right now that is just a bit too easy to do, all you need is an hour or two of RP on an alt to pay for 6 hours of whoinvis that you can easily spread across many days.