I think the BattleTech cartoon was probably as close the franchise came to making the mainstream of popular culture. I could include the videogames (which I have discussed before) but the cartoon took place during a time where big fighting robots were generally in the mainstream anyway. MechWarrior 2, Robot Jox, and of course blockbusters like Terminator 2. Even Japanese distributors were beginning to test the US market with titles like Patlabor and different flavors of Gundam. Big robots were beginning to become as much a staple of science fiction as the space opera. (Some media, like Gundam and BattleTech combined the two).
So how does one market a mech-centric space opera towards children? As seen with other US franchises like Exosquad, don’t sugar coat it. In space operas, there are big wars going on, and people die. 1st Somerset Strikers doesn’t show death like Exosquad does, but one of the plot developments banks on one of the major characters failing to eject from his devastated BattleMech before it explodes and being thought dead by his compatriots for most of the season. Likewise, though it specifically mentions in the official BattleTech canon that the Jade Falcons evacuated the city of Romulus before glassing it with orbital bombardment, it was never brought up on the show. So the viewer thinks they just watched an entire city of people get vaporized. Heady stuff. I really wish they had made more of a deal of the destruction of Edo on Turtle Bay later in the season, considering that most of the inhabitants in fact WERE massacred by the Smoke Jaguars (one of the reasons that clan was targeted for termination during Operations Serpent and Bulldog)