Currently, we get these options (about land -> options) :

• Create Objects : [X] All Residents [X] Group
• Object Entry : [X] All Residents [X] Group
• Run Scripts : [X] All Residents [X] Group

I propose replacing these options with :

• Create Objects : [X] Unverified Avatars [X] Verified Avatars [X] Group Avatars [X] Objects set to group [X] Other objects
• Object Entry : [X] Unverified Avatars [X] Verified Avatars [X] Group Avatars [X] Objects set to group [X] Other objects
• Run Scripts : [X] Unverified Avatars [X] Verified Avatars [X] Group Avatars [X] Objects set to group [X] Other objects
• Emit Particles : [X] Unverified Avatars [X] Verified Avatars [X] Group Avatars [X] Objects set to group [X] Other objects

This replacement extends the land permissions system, making it more flexible and thus easier to use to prevent griefing, without having to use draconian settings which are a pain for everyone.

For example, we can allow build for verified avatars, while keeping it off for unverified avatars.

This allows us to, for example, stop griefers rezzing things, without stopping our verified guests rezzing things.
Convenient for most (verified) SLers, but good for preventing griefing.

We no longer have to ban all unverified avatars from our land to prevent griefing there.
Instead, we can simply limit what unverified avatars can do until they verify.

For sim-wide protection in the event of sim-crashing weapons being used, there should be a region/estate-wide toggle that forces the "unverified avatars" box to be unchecked. This allows landowners to give permissions to group members and/or verified avatars, but not to everyone else. This effectively puts a halt to anonymous gatecrashers spoiling the party.

The two big changes that I'm pushing for with this proposal are :
1) The ability to stop day-old, unverified, no-payment-info-on-file avatars from covering an entire sim with particles.
2) The ability to stop that same unverified resident from crashing the whole sim using a single buildable parcel and physical objects.

This proposal would neatly address the two major types of griefing in SL - particle spam and sim crashing, both by new unverified accounts.

As a bonus, this proposal would not force landowners to change anything. It would simply provide the option for heavily-griefed places to enable such features.
Further, it would avoid causing unnecessary inconvenience to residents by targetting the most likely griefers (new, unverified accounts, as opposed to 'non-group' accounts in general)... and the most likely behaviour of griefers (building or creating large particle effects using a throw-away anonymous account).

I don't want to create a culture whereby unverified residents face permission errors across the grid when they attempt to build or use particles.
What I want is for the major clubs and social venues of Second Life to be able to stop these very common forms of griefing, which currently have no technical solution.