I agree with your general approach - use the minimum amount of words necessary to a) get your meaning across and b) communicate clearly with your audience (this required you to know your audience). This second rule might mean you have to increase the number of words - it's a balancing act.
However, I don't think either of those sentences are grammatical, and they don't even make sense. For a start, you don't "construct architecture" - architecture is the design, or the design process. You can look at a building and say it has "beautiful architecture" but that's like saying "I love the design". Architecture and construction are two separate stages of creating a building.
If we were to fix this problem by saying "building" instead of "architecture" (since the construction of buildings is very standard driven) your first sentence would be
"The system is responsible to define standards for the construction of the building."
This sounds badly translated - you would say "for building construction", not "the construction of the building". Also, we say "responsible for", not "responsiblefor": "responsible to" means that you can be held responsible by that other thingparty - eg "The president is responsible to all voters, not just the ones who voted him in."
For a short version, I would write
"The system is responsible for building construction standard definition.", or if you thought this was a little difficult to parse, you could say
"The system is responsible for defining standards for building construction."