You are right in that Roaring Primadox is perhaps a little weak. However, without dropping about $100 into the game (hard to do on a student budget) it is going to be difficult to get the Restoration Angel or the Sudden Disappearance into my deck.
Also, in the case of Sudden Disappearance, it is a 6 mana card for a one off effect. Whilst it would indeed mean that all the triggers would indeed fire at the same time, it is a very expensive card for a similar effect to the Roaring Primadox, especially when you consider it can only be used in my turn rather than as a response to another player's actions.
Restoration Angel is another card that is very very good. But again for me the idea is to be able to make whatever triggers I have fire repeatedly. If I can use the Azorius Arrester or Azorius Justicar to detain the larger creatures, then the rest of the game each turn becomes more and more simple. Keep in mind also that using cards such as Acidic Slime, it is possible to create a situation where the opponent is mana screwed thanks to my removal of their lands, therefore making that another method to theoretically create a win.
I have also looked at the heavy reliance that the deck has on the Primadox to function, and believe that using Ajani, Caller of the Pride, I can shore up that reliance and hopefully make it so that the lynchpin is harder to kill. All that needs to now happen is for me to work out a way to get more loyalty counters onto Ajani, Caller of the Pride, if such a thing were possible.
In other words, using creatures such as thragtusk to create creature tokens and give me life in such a way to draw the game out long enough that a small army of tokens from both the Thragtusk and Geist-Honored Monk will be able to chip away at the life total of the person, and also at the same time act as a defensive screen for larger creatures.
It might not be the strongest deck in the world thanks to its heavy reliance on using the Roaring Primadox for its effects, but I believe it will be a fun one to play, and thus all that is currently stopping me from playing it is the lack of a side board.