FAD Game - Almost Unstoppable Heavy Power Armour

I've just got home from my local club (HDWS) having had another game of FAD with my friend James. As we are still getting used to the rules we had a loose scenario of the local militia on a out-flung planet calling in the cavalry after being attacked by some off-worlders. The sides were as follows:

James (unwashed off-worlders)
1 x Walker,
2 x large Heavy Armoured squads,
1 x small squad in Power Armour
1 x HQ in Heavy Armour.

Myself (good guy cavalry coming to the rescue)
1 x Militia unit of 20 conscripts,
1 x Heavy Power unit with double barrelled weaponry,
1 x Improved Armour squad of 10 men,
1 x HQ of 4 men in Heavy armour.
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Both sides were pointed out at approx 500pts each.
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This was the first occasion we have used a Heavy Power Armour unit with twin weaponry in a game. Suffice to say, the unit was virtually unstoppable, and as well as being very difficult to kill laid down totally overwhelming firepower !
Here it is taking on James Walker...
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We need to think about how to use units such as these in a playable way in the future, by possibly either downgrading both their armour and firepower.
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