A 2/3 with deathtouch is great in UB, especially since the game plan against aggro is usually to stabilize early, trade up efficiently, and start generating card advantage
Going through this set-by-set is fairly time consuming, but its worth it because at the end we will have set aside a much, much smaller block of cards that will constitute our collection (until the next set is released)
It is an extremely efficient removal spell
I think, ultimately, that is going to be too expensive and too inefficient as a card draw engine
While you need burden counters on The One Ring to actually draw a card, which technically is a restriction, tapping it puts a counter on it before you draw, so unless theres something like a Solemnity out, there is no restriction here