I'm of the belief that in the modern age there are plenty of resources to go around, but human nature (being the root of all evil that it is) continues to foster socioeconomic stratification. Simply put, people have always found excuses to kill each other and, until such time as technological singularity saves us from ourselves, will continue to find excuses for killing each other, irrespective of scope.
It's a sad reality, but there are no trends in all of history to suggest that we're ever going to get along just because the entire universe is our collective oyster. And that's not even considering first encounters (Columbus, anyone?).
My personal opinion is, that it would be nice for testing and have the option, aswell some weapon systems ingame (lasers, coilguns/gauss guns as slow firing heavy hitters and railguns as rapid firing guns, aswell rocket/torpedos and possible aswell plasma canons for short distance and/or as defence weapons to shoot down rockets aswell), aswell some armor plating would be nice to have in the game. I personally would like to equip my ship with some weapons, but Space Engine is very good fitted as exploration game how already mentioned and should include the possibility for at least the single player mode and possible possible a private server to disable hostile npc ships, if there would be some in the future and combat in general. If this would be possible on the fly and with some editor tools ingame (like the one in the planetarium mode), we could even test the defence of our ships when we want it by spawning a npc testship. ^^
Aswell it would be good against the phobias we all have in some way for space how mentioned in a specific thread, when our ships are armed to the teeth. Not that we plan to fire on some aliens or so. Only on gasgigants, black holes and empty dark space.