I think the arena model looks really interesting, and I'll be glad when its available on PC.
And, you've got to be realistic. MS are giving FD money for exclusive content for ED on XBox. More money for FD means a better overall game. Hopefully FD will be able to balance the investment so it doesn't just go into arena/xbox improvements.
You are right about realism, but FD do keep changing the rules of the game... If you are an Alpha backer who was under the impression that you would continue to have first access to new content you have a right to question this move.
Personally I figured once Alpha was over that was it in terms of exclusivity but then Beta was sold on the back of the exclusivity promise... Test the new features before they go onto the main server.
Now we have xbox timed exclusives which are only accessible in the short term if you buy the game again. Realism is all well and good but you can't keep moving the goalposts and not expect a reaction.
Does it matter in the infinite scheme of things? No. Are there more important thing in life to worry about? Of course. But realism also involves perspective and from my perspective a timed xbox exclusive is not in the spirit of what was promised at PC Beta level.
And to those who are saying this is a different game... That is not realistic in the least.