It was a nice idea but developed baddly.
There was already a idea from Jason's book (building upon older elements) that the Firestorm matrix doubtlessely already had other hosts in the past, from other planets, etc. It was more than a mere metahuman power.
The Firestorm Protocols were a nice addition to the mythos in that they were a great analogy with nuclear proliferation - a great world-shaking power, becoming more and more common and less restrict, finding its way towards people who may be too dangerous or incompetent to handle it. The Rogue Firestorms were essentially living suicidal dirty bombs.
I think the mistakes there were making Firestorm not actually be the first - in a way, Firestorm is just another knockoff. The Protocols should've been based on Firestorm the original. Firestorm protocols should've come along once Firestorm was better estabilished - the original, accidental one vs the mass-produced, industrialized Firestorms. And not all these guys are evil suicidal dirty-bombs, even if they are wielding great power that may be dangerous, what to do?
There was also too much angst in that book for my tastes. Needed more cast estabilishing, world building, etc.
Pohzar was downright villanesque in that story.
They could've been explored deeper as well. Firestorm is not just a perfect weapon of war. Imagine every country having a nuclear man capable of making any material he feels like. Sure, oil is probably out (hidrocarbon, so organic - or not?) but imagine infinite supplies of Titanium! Promethium! Helium! Uranium! (yay, infinite nuclear power!) Thorium! Kryptonite! Graphene! Ethanol! Carbon Nanotubes! And it goes on and on.
In fact, I don't get why we never saw Firestorm or its hosts use the power for material gain that helps people. Nothing wrong with a honest Firestorm supplying some rare material that helps people and getting some money from it, a super-hero gotta eat and pay his bills. Say, making enough ultra-thin ultra-resistant material to build a space elevator. Dessalinize water into drinkable water. Fix oil spills. Or make enough ozone to seal the ozone layer, Or safely dispose of chemical weaponry by turning deadly nerve gas into water vapor. Can Superman turn nerve-gas into water vapour? Thought not.
A villain (Deathstorm?) with the same powers could use this to, say, give enriched uranium to dictators and terrorists willy-nilly. Or create immense stockpiles of chemical weaponry. Or flood the market with so many preciousm materiais that it causes economic ruin and unemployment. Or increase global warming by making a lot more greenhouse gas. Or simply turn rocks into sea-water until the world floods. Or turn the air into Joker Toxin.