The most confusing part of morph for people I've found is the stack(less) exception. Everyone wants to respond to the morph trigger. Didn't that go to the stack?? I've heard that many times. It's not a new player friendly mechanic.
I think the mystery aspect of morph is overstated. You only play a morph because you are either getting it in play faster or un-morphing gets you something better than just playing it straight. What the card is doesn't usually matter. See a morph, kill it. Almost always a good idea. Maybe it matters if they have open mana to un-morph and you have to wonder if it's Stratus Dancer or Exalted Angel (i.e. will my magma jet kill that). Or the questionable shit like Ire Shaman (is that worth a removal spell?). The only morph that you feared to kill was Willbender, and I had him in my cube for the longest time just because it was such a sucker punch to flip that on someone's removal spell. But the card is just bad outside those moments (and most cubes are probably too fast to be trying to setup that play these days).
There are never going to be enough playable morphs to create true mystery in your average rare cube. Morph is more like suspend I think. People generally know what's coming, and morph is only delaying it like time counters. Morph is pretty clunky honestly. The angel will probably always be in my list because she is great, but everything else is pretty expendable in my mind. Although Eternal Witness morph has been pretty good.
I think the mystery aspect of morph is overstated. You only play a morph because you are either getting it in play faster or un-morphing gets you something better than just playing it straight. What the card is doesn't usually matter. See a morph, kill it. Almost always a good idea. Maybe it matters if they have open mana to un-morph and you have to wonder if it's Stratus Dancer or Exalted Angel (i.e. will my magma jet kill that). Or the questionable shit like Ire Shaman (is that worth a removal spell?). The only morph that you feared to kill was Willbender, and I had him in my cube for the longest time just because it was such a sucker punch to flip that on someone's removal spell. But the card is just bad outside those moments (and most cubes are probably too fast to be trying to setup that play these days).
There are never going to be enough playable morphs to create true mystery in your average rare cube. Morph is more like suspend I think. People generally know what's coming, and morph is only delaying it like time counters. Morph is pretty clunky honestly. The angel will probably always be in my list because she is great, but everything else is pretty expendable in my mind. Although Eternal Witness morph has been pretty good.