Blah, blah, blah, Alpha Strike this Alpha Strike that...
...Okay, the discount on units which can only shoot in Short range is an absurd idea. I've abused this to its limit with the Fire Moth H (A unit with a 26" movement that can deal 5 Short, yet is somehow under 15 points?), but the basic Charger shows the ridiculousness of it.
The basic -1A1 costs 18 points, yet has A5/S6. A 300-point list could fit SIXTEEN of them on the battlefield, and while they have no poke beyond Short range, that's not what they'd use anyway - it'd be 4-point melee hits all the way, or 5-point charges. With no need to worry about shooting, they'd take Sprint actions to get across the battlefield and simply swarm over the opposition. The other horrifying part of it is that they're all Scouts, meaning they have easy access to the Maneuvering Ace SPA if they're in a Recon formation - 8 of them being able to ignore woods/jungle?
My usual go-to "Is this balanced?" list is an equal PV-worth of MAD-3Ds, which would be 8 of them, 2 of which could be upgraded in Skill - or 7, all of which would be upgraded. Once the Chargers got in there the MADs would be slaughtered - even allowing three rounds of shooting before the melee started the MADs would have downed 3-5 of the Chargers and still be heavily outnumbered by units that are as tough and deal more damage than they do. Charges, in particular, could easily destroy a single MAD in a round if three Chargers connect.
I have this sudden, hilarious image of a pair of Chargers playing "Goliath-tipping."
So, yeah. Most of the Charger variants are pretty good, but if you want to break the game, try for an Ork WAAAGH! list.