Yes but how many to capture an intact planet most of them have 2000 colonists so it can't be a lot more than that. I would rather just come in and capture it whole
. Too bad that you can't get tech advances from capturing planets if we are limiting all the diplomatic ways to capture tech. Well I guess there is always Intell to get tech and capturing the colonizer ships for the colonization techs.
Hmm the racial traits picks are a lot harder choices if you have to use intell and maybe even have a few fights with the AI. Although without a bonus its research is real slow so it will take a while before it actually has any real weapons.