I am not sure how I feel about Gifts and its sister Intuition. In theory it's this very interesting quadruple tutor that severely tests the skill of pilots and deckbuilders, in practice it often either just combos (the crude versions with Rites + fatty or whatever) or isn't worth it, as getting your 3rd and 4th best cards at the expense of your best and 2nd best is a steep cost. Cube does seem like the perfect place for sweet "value" piles like Loam / Crucible / Snapcaster / Gravecrawler, but, even if you can build this kind of deck, you also have to not draw those cards, and so on.
Another idea is that tutors of this restrictive and multi-card variety suffer in 40-card decks. There's not enough room for your targets, you'll draw them, and so on. GSZ for example is a pretty strong card in Cube, but in Constructed it's the strongest tutor printed since ... Gifts, or if it's stronger than Gifts, since Intuition.
edit: fuck capsize though. no conflict there