Various newbie questions

[Jumpp (OP)]

I recently found an NPR colony a couple jumps from home.  When I conquered it it turned out to be the homeworld of a low-tech civilization, the Musa.  When my armies finished taking it I found ~560 million population and a few maintenance facilities, but no other structures of any kind.

Were other structures likely present but destroyed in the fighting?

How did these guys end up being so primitive?  I gather there's some random variation in the strength of NPRs.  Is it possible for NPRs to be born at Ewok levels of technology and to stay there for decades?

The default universe size is 1000 systems.  Given the slowdowns I'm seeing with only 80 or so systems explored, this seems unimaginably huge to me.  Do people really play at that size?

If I do a Conventional start instead of a Trans-Newtonian start, do the initial NPRs start conventional as well, or am I giving them a big head start by doing this?

Does the "Starting Tech Points" setting have any effect on the starting NPRs?

(When I say "starting NPRs" I'm talking about the guys created via the 'Computer-controlled Empires' section of the Create New Game panel, rather than the ones that result from exploration and the 'Non-player race generation chance' under the Basic Parameters.)

[Nathan_]

There are some conventional empires that get spawned so that you can cut your teeth on ground combat without fleet intervention messing things up. That is surprising that they had any facilities at all, but if they were a true TN power they'd have had more. Most NPRs start as TN powers, so you starting at conventional levels gives them the advantage.

[Jumpp (OP)]

Would these conventional empires still exist even if I set the Non-player race generation chance to 0?  I'm thinking I'll do that on my next game, to slow the onset of heat death.  I was thinking that a 200-system universe with 3 starting NPRs might make for an interesting game.  But these little pre-spaceflight civilizations are cool, and I'd miss them.