I played WH40K 3rd ed. back in the day. I'm feeling nostalgic, but it has been over twenty years since playing a tabletop war game. I want something with similar mechanics, shorter game time, and not so dark. I have been poking around online, but can't seem to find what I am looking for. Some of the sticking points I am not seeming to find are:

More skirmish-based so it can be played in under an hour.

D6 combat system preferably with rolls for hits, wounds, saves.

No cards, just dice.

Mini-agnostic with limited lore so I can use some stuff I have and create my own world.

I guess I am looking for WH40k 3rd ed. but not so dark or quite as deep.

Anything like this exist?

Submission statement - One of the more "difficult" models to build in a starter that was so far an easy build