Volume wouldn't directly equate proportional numbers of people. It seems to be a habitat rather a coffin hotel to the stars meant to naturally expand the population SOMEWHAT as the generations roll by. Lots of the volume is going to be life support for a living biosphere as well as facilities for limited food production. If this is a non-suspension population they absolutely need all the essentials of a world and community especially work and recreation to keep mind and body healthy and at peak and prepare their decedents for the colonization. This also, and may especially, go for the gene pool so cross contact with all modules would be essential. Then again look how communities on Earth only miles apart or neighborhoods blocks apart can become islands of local behavior and even animosity. Separation of any sort could be the wrong way to go except for a Traveller game. I would prefer the cylinder approach , one for all.