Democracys tend to be more stable than dictatorships. And hugely more effective. And as @Eternal well said, stability at the cost of everything else, is not the objective. And of course, meritocratical systems tend to be hugely more effective too.
Concerning antinuke. I agree with words of @archsimkat. But I point out, that not having mobile antinuke, seems to make many massheavy maps totally turtle type (some DualCap, Astro?). Once your army or navy value is bigger then value of nukes neccessaire to destroy that army or navy (so that army/navy cant dodge those nukes). It forces the games to go into "build big gun, everything else does not matter" style. Having mobile antinuke could add lots of possibilitys and gameplay. And reduce turtle-eco-build-big-gun, type of games.
I am not talking antinuke on nukesub, but maybe new unit that could go on land and water. More expensive than static one of course, but maybe reduce the price of static anti nuke a little?