Ok though here me out, Mega Lopunny is actually really good design. First, it actually looks like a proper evolution.
The problem with most megas is that they are overdesigned. Too many knobs, bits, colours, phalanges, etc. Tyranitar and Steelix are good bad examples. And/or they just become ridiculous and hard to take seriously like Garchomp or Sharpedo.
Just imagine the silhouette of each mega and you can see why the design often falls short.
Lopunny has a subtle upgrade in design in comparison. It looks tougher and more aerodynamic. The new typing (Normal/Fighting) makes sense.
The design also incorporates ridiculousness in a subtle way. Clearly it’s a reference to the 1980s workout aesthetic.
You got the arm and leg warmers and tights. Fortunately they opted to keep the colours simple though!!! The large bow and scrunchie look is also included!!!
So subtle, so cleanly incorporated, iconic silhouette, logical upgrade, 10/10 design.