By itself technocracy has no impact on the advancement or level of aggression a nation has. The difference between technocracy and democracy is in how you choose and oversee people in doing the government not in what the government does.
That said you could argue that technocracy would almost always be more advanced than a corresponding democracy since running a technocracy requires better communications which usually implies higher technology. But it is not a causative link from technocracy to advancement, rather better technology allows more advanced and extensive technocracy.
Similar argument applies to the pacifist nature of technocracies. A technocracy is a solution for efficiently handling predictable and repeating issues that are within the competence of the technocrats. As such it only evolves as a general solution to government in stable and peaceful conditions and will generally avoid doing things that would put the society outside those stable conditions. But it doesn't cause the stable conditions and stable conditions do not imply peace.
There are lots of empires in the history which for relatively long periods had stable expansion by conquest and had economies and political systems adapted to that. A technocracy evolved under such conditions would try to maintain a steady state of controlled and managed war with only brief periods of peace before the next war.
And, now that I think, the same would apply to technological advancement. A technocracy would try to maintain a steady rate of progress similar to the rate it evolved to manage. A technocracy evolved during a period of rapid technological progress would naturally be equipped to support and maintain rapid technological progress and end being advanced. A technocracy evolved during a period of technological stability and regression would not have a strong interest in technological advancement and would end up technologically retarded. Same applies to other aspects of society.
Which is why a technocracy is not a good solution as a monoculture. It is simply too stable to adjust well to changing conditions and requirements. Realistically an "advanced" government would mix it with something that is reasonably dynamic but is weak in handling long term stability and planning.
Democracy is one such system. The EU, for example, is a technocracy not because anyone things it is the best way to manage things, but because that best compensates the weaknesses of the democratic national governments in handling the long term planning required for something like the EU to function. The downside is that if you consider the EU in isolation of the national governments — or worse, in opposition — it simply won't make any sense.
Any really efficient system is a mixture of different solutions for different issues. And has the flexibility to change solutions as needed. Avoid monocultures, indeed.