So apparently I deleted a comment on my MtG Origins Set Reveiw which I entirely didn't mean to and now I cannot get back. I not saying it is impossible to get back, just that I am suitably inept with computers to do so. The comment was to the effect of why do I not review cards like Wilt-Leaf Winnower at all, Nissa's Revelation only in a couple of lines yet waste loads of time talking about limp commons such as Topan Freeblade. This is a good question.
To get a good drafting cube you want a spread of casting costs across your cards that reflects the average mana curves of the commonly built good decks. This means that there should be far more one, two and three converted mana cost cards than any thing else. By the time you are getting to five six and seven there really are not that many slots for cards, even in a big cube. Mine is about 600 cards presently and there are about three six drops per colour. Power per mana goes up as you increase the CMC of a card however the bar for a cube viable card in terms of power per mana goes up far more steeply with increasing CMC. A fine two drop might make it, a fine seven drop won't, it has to be exceptional.
So lets talk about the two cards in question I under-reviewed. Firstly the Wilt-Leaf Winnower, a card that is clearly powerful. It will be a limited bomb and might well see a bunch of constructed play, if for nothing else because it is good against Rhino. For cube however I don't think it will get a look in. It is a five drop so as per my previous logic it needs to be very good but this is not the whole of the picture. Cards need to do things, you play them in one of several roles, threats, removal and so on. Winnower is a value removal spell as well as an OK threat. That is its role, you play it when you want all of those things condensed into one card. Commonly in grindy slow decks like the Rock. The problem this has is that it is worse than enough of the cards that fulfil the same role as it that there is no place for it in cube. Skin Render is cheaper and has no targetting restriction. Shriekmaw has far more flexible costings. The list goes on longer before I get to Winnower. I am being overly harsh to the card, it is much more playable than some of the things I take the time to review. It is just because the card offers nothing new and with not quite enough bang for a high CMC that I so readily disregard it.
Nissa's Revelation is incredibly powerful potentially but it is pretty much just a card advantage spell and a risky one at that. Scry five is a lot but you still need to be playing too many fatties for this to be reliable and worth the price. For that sort of mana and trouble you can just win the game. This might be the most powerful card draw thing in green but it is in the wrong place entirely. If you need card advantage use cheaper things that are not quite as pokey as this instead and save your top end slots for things like Craterhoof Behemoth. Although I don't think this is powerful enough you could argue otherwise and that is fine, the primary reason this doesn't get much cube consideration from me is simply because there is no sensible place for this card. Not because it has directly better comparable role fillers like Winnower (although again, I would argue that there are!) nor because it is not powerful enough.
So finally, why do I bother talking about really clearly awful or underpowered common cards. In the case of Topan Freeblade I fully accept I need to stop. It is automatic when I see a card that would have once been good enough to think about it in the context of cube. For other weak cards, if they are the cheapest or cleanest way to do a thing, or they offer reasonable redundancy to another useful thing then they usually get talked about. If you don't think about the weaker or less obvious cards then they are the most easily missed!
I hope than answered you question Dan H Tran and my apologise for deleting your comment.