Can someone explain why i act last in combat when my ships are much faster due to augmented engines?

Did you enable ship initiative? If not, the attacker will always fire first

How do you enable that?

Once you start a game, go to "game", then "settings". You can enable Ship initiative in this screen

Thanks, i guess that was turned off by default.

Ive started using the VDC mod and ive noticed that late game combat is simply stellar converter spam. It does so much damage and you cant dodge it at all. All you can do is mass it and try to be the first to fire.

Also planetary defenses all become pointless when a single stellar converter blows everything up and wipes out most of the population as well.

I find the best thing against missiles is getting better armor. You can never have zortrium armor too soon. I'm also a big fan of neutron blasters. Once they've miniaturized a bit to where you can fit 8-10 on a cruiser without trouble they're good against missiles as well as keeping some offensive potential. And then level 5 shields in combination with zortrium armor means you almost don't have to worry about missiles anymore.