A feature where if someone is suspended or banned, instead of simply disappearing from the search tool results, they still show up but their account status reads 'banned' or 'suspended'.
Also, every profile has a link to 'account history' which shows both good and bad things that have happened to that account, e.g. past suspensions (with reasons), past awards, past major SL-wide contests won, etc. Also, the ability to limit access by account status (e.g. "disallow anyone who'se ever been suspended", or "limit access to people who've done something majorly good for SL"
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Griefers and minors being actually banned from SL. Abolition of the 'abuse report' system on the grounds of uselessness. Abolition of all the "community support" Lindens and in-world help groups, in favour of large banners being displayed at the top of the SL client which read "Do you have a question? READ THE MANUAL". All the people that were involved in the above jobs/teams would be re-allocated to writing up "The Manual". This would teach everyone to read the manual first, thus, over time, helping them learn a lot more information and reducing the burden on all mentors/instructors/etc and LL employees alike. Some residents would get fed up, and leave, and this would be a good thing because people who refuse to read the manual at all are not suited to survival in a virtual reality anyway.
All the proposals in the feature voting system which have more than 200 votes being fully implemented, instantly. The job of deciding how to do this (especially where multiple votes have over 1000 votes each and are exact opposites of each other) should fall to a random troll on the forums who complains that the Lindens are not doing enough of what they want.
Lag disappearing, completely.
Sims never crashing, and being able to hold an infinite number of avatars at once.
A "Movie Theatre" in SL where the Lindens put on one movie a week (legally) to attract people to watch video in SL. The first video shown should be a Monty Python video.
Everyone having infinite money, which they could cash out into RL money if they wish.... which also kept its value and diddn't result in astronomical inflation or suspension of the LindeX.
Technology to advance so far, so fast that we could abandon computers and jack into SL with plugs that connected into our brains, like in "The Matrix". (sorry for referencing it)
It'd enable everyone to live the perfect life full of pleasure and happiness for as long as they wanted, whilst ignoring their RL (or simply arranging to never go back to it and to die after a certain amount of time in the virtual world).
The laws of physics in SL applying to RL would be nice. I'd love to be able to fly around IRL, never have to pay money for food or shelter, be able to teleport and be immortal.
These ideas are all impossible, insane, silly or trivial. Don't take any of them seriously.
