I felt the same way with MP Grimlock... it just seemed to be an up-sized Gen1 toy with more articulation. MP Soundwave is likely to be the same, for all it's simplicity of just turning into a squarish block in both toys.
I like that there will be some MP toys that are more "playable" than "puzzle"... in that, these smaller ones are quick enough to convert to play with them, and not just sit on the shelf after a couple initial conversions.
The MP concept should indeed be more "puzzle" than "play" in general, but it's difficult to imagine that the smaller ones will be able to be engineered into anything super-spectacular if they have to remain in-scale.
I think these have the right balance... so look forward to getting the complete set of 'Con & Cassettes.