There was a thread putting forward this kind of idea a while ago, shortly after launch if I remember correctly. There was a lot of nay-saying, foretelling of doom and the general sort of idiocy one would expect. But as I said there, I think it's a great idea that can only improve the game for all.
I'm not a PvPer, I trade and bounty hunt NPCs and the one time I did hit another commander it was by accident and I withdrew from the Nav Point to pay my fine. I don't want to ruin anyone's day or set them back on their path to their dream ship. But if there was an arena where one could go and have some fun with like-minded commanders without putting one's whole bundle on the line then that would be very welcome indeed and I'd like to take part for a bit of excitement.
For those of you who want PvP in the main game, it's good for you too. As it gives people a place to learn and find if they enjoy that sort of thing. Without putting their entire credit line in jeopardy (I would hope).
For those who want no PvP at all under any circumstances, well, you can avoid it entirely and hopefully it'll take some of the ne'er-do-wells away from wherever you are. Worst case scenario you still have solo.
When you also consider that an arena could be set up to use dedicated servers (no idea if it will be) you could have the perfect mix of quality entertainment with a really good space sim dog-fighting mechanic - which I feel is one of Elite's strengths.
I honestly think it could be the thing that saves Elite from the abyss.