Starlight Express/WMG

Control is Master Hand.
Canonically, the events of Starlight Express are a little boy's dreams about the anthropomorphic personifications of his toy trains, who live to race one another for bragging rights. The general consensus on the storyline of the original Super Smash Bros is that Master Hand represents a child, and that the characters are his dolls, which he forces to fight each other for his own amusement. (The game over screen, which shows the player character in the form of an inanimate toy falling to the floor, supports this hypothesis.) Control introduces each National engine as he appears, just as Master Hand announces each fight. Neither Control nor the child to whom Master Hand is attached appears physically, but each orchestrates the proceedings while he can. Finally, Starlight Express ends with the toy trains successfully demanding that Control "shut it" and presumably forming a self-sufficient society, while the original Super Smash Bros ends with the player character triumphing over his cruel juvenile master by effectively killing him and claiming his place as the superior doll.

Therefore, one can reasonably conclude that Control and Master Hand are synonymous. If this hypothesis is taken into conjunction with the notion of Tabuu as a figure of authority over the child, then Tabuu is Control's mother. Moreover, a chronology of events in Control/Master Hand's life seems possible to construct: the child began as a junior railroad enthusiast and Nintendo fanboy, with the former interest predominating, until he grew slightly older and became more interested in video games. (In some productions of the show, the Japanese train is named Nintendo.) Always somewhat unstable, the child finally snapped by the events of Super Smash Bros. Melee, in which the hemispheres of his brain, represented by his two hands, were completely given over to imagining his toys as real--and threatening. His condition worsened by the events of Brawl, which contained more elaborate and nonsensical stages and scenarios than even the previous two games. By then, the child incorporated fragments of his old obsession with mechanical life into his play; witness the inclusion of R.O.B. and Mr. Game and Watch.

Perhaps "seeing the starlight" has a more sinister meaning than the songs indicate.

C.B. isn't just in it For the Evulz.
C.B. seems to indicate that his constant team killing is just for kicks. But on the other hand, when Dinah is dumped by Greaseball, he sings "There's Me", which since we find out later that he is notstable comes off as a bit stalker-ish. Is it possible that C.B. is actually acting deliberately, eliminating engines who might stand between him and Dinah?
 * Old 97 probably wasn't trying to woo Dinah.