I wish modded characters weren't so overpowered, in general. Every one of these characters outclasses any of the original SRB2 characters in regular game play, in my opinion. Although, I am sure some would argue with me on this point because the strength of their abilities does not seem overwhelming, as with some other modded characters.
Specifically, every character seems to make platforming too easy. I have a Apple mouse which makes using Dirk's abilities difficult, but it seems that theoretically, once mastered, Dirk makes his own platforming via forming ice blocks and skating off said ice blocks (and then making more ice blocks after jumping off the skated ice). Whirl jumps high and his double jump's gliding effect also makes platforming relatively easy. Vesola's double jump also launches her really high, which is only strengthened by her fluttering, slow aerial descent.
That stated, I have to give this 5 stars because of the innovative moves with strong synergies.