The original Modern Masters definitely had some linear, poison principle-y themes, but at least with the commons, I don't feel it led to drafts as on-rails as the current set. Many of the
rebels were useful outside of the dedicated archetype, as were some of the
faeries; you could play
arcane spells without caring about the splice clause;
suspend creatures were just generally efficient bodies; many of the
thallid producers came with bodies at an acceptable rate. Sure, giants, affinity, and dredge were narrow, but there were only three common dredge cards, and a few of the common giants were fine as french vanilla creatures.
Contrast that with Modern Masters 2015, where all of the common spirits are useless outside of the dedicated deck; the equipment is mostly overcosted so as to go to the RW drafter; affinity is still affinity; most of the bloodthirst dudes and bloodthirst enablers only play nice with one another; the token makers and token payoff guys are too expensive to be worthwhile for anyone else; and so on. Maybe there are some sweet brews enabled by the rares and mythics, but the commons seem to steer you down a very particular route, to the point where you can ignore the majority of cards in your own colours if they're not for your prescribed archetype.
To give a very specific example from my GR draft yesterday evening: of the
17 available red commons and 17 green commons, there were exactly
three playable red cards and
four playable green ones for my deck. So I was passing far more red and green cards than I was taking, and only four or five of my picks in the draft had any semblance of tension. I don't recall getting this feeling from my half-dozen or so drafts with the original set.