I just imagined an Awesome with Hardened armor and peed a little. That would be scary as hell.
One of many designs where the weight savings from DHS does some amazing things. You can keep the mech identical except for a HS swap, not even bother with ES or an (X)LFE, and nearly max out the Hardened Armor cap. BV2 goes from 1605 to 2064, to give a quick sense of how much you've just improved the mech, and the price difference is only about 600,000 C-Bills.
When I get some time, I may post some Hardened Armor designs over in Fan Rules, just to play with this idea a bit. Simple upgrades(and there are none simpler than DHS swaps in terms of effect on the unit) are a fun little design area.