Unexpected Windfall earns its place by drawing the player two cards and generating two treasure tokens (which tap and sacrifice themselves to generate one mana of any color each)
A Sapphire player on turn one can easily play an item like Pawpsicle for 1, draw a card, then destroy the item and develop a 3/3 immediately
Once you do its hard to remove and even harder to kill in combat, and it can give you a winning boardstate in a single swing
Arch of Orazca seems like the most profitable way to gain advantage by having a lot of extra mana, but I could see playing a couple of small packages that combo well with Hour of Promise that allow you to do other things
1 Reanimate At half the cost and some life for all of the reward, Reanimate is the best reanimation card in all of Magic's history and properly so
At conventions, expect to fill out a short form, possibly wait in line, and spend some time while the buyer reviews everything