One

Probably best not to ask the advice of wankers, they're usually complete tossers.

I think that if you believe complexity shift happens after the prologue then releasing it to that point could have a few consequences. People play the prologue and form an opinion on the game, either positive or negative and choose to continue or not when it comes out. You release the later sections and people who liked the prologue are suddenly faced with a much more complex organism and react in two ways, walk away as it wasn't what they were expecting or enjoy the growth and the change of pace.

The problem is that you'll already have lost some of the people that may have enjoyed the more complex systems and gameplay before they know that it will be coming later. You'll need to either make it very well known on the gamepage, or and this is a better option include some form of hook at the end of the prologue to hint at what is to come.

Personally I think a longer first release is a good idea as it gives more of a taste of the game, but you have included a caveat which does raise problems of it's own, as long as you can address those in some way that allows you to keep the maximum exposure you can then I think you'll be fine to release it.