Arcee has been shown to be reckless when it comes to the whole "My partners are DEEAAAAAAD!!!" thing. She want her revenge and whatnot. Depthcharge also had his revenge obsession with Rampage. If you watched Beast Wars, I'm sure you remember how that worked out for him. At this point Arcee is showing very little character change when it comes to revenge. Maybe it's too soon to say but Arcee's character may remain static in that regard. If that is so, then I could certainly see her dying in a similar way to Depthcharge. Maybe in a fight with Airachnid or Starscream. Since Arcee is such a main character if her death was pulled off in such a way it would have to be very well written. I could see this happening at the series finale. The writers seem to have balls enough to kill a main character. If Arcee's death was done correctly it would have a great impact given how much she will probably be developed.