I was just having a thought on the MP Soundwave topic...

Maybe the designers are looking to focus on the first year of Transformers, to "complete the set".
Even though they could do with breaking up the run of Autobots, they have done all 10 first-year Decepticons, but only 4 of the 18 first-year Autobots... leaving 14 more to go.
MP Minibots? Why not... we had MP Cassettes.
Maybe some 2 or 3 packs of MP Minibots like the Cassettes would go nicely.