Research in the game are fairly abstract and you need to impose personal restriction for it not to become too gamey, in my opinion.
I would not mind if research at some point became a bit more dynamic and fun.
Right now you don't really have any education level of the population which should be something that limit the amount of research complexes you could build and utilise. I also think that you should separate civilisation spanning research from more military applied sciences and they should perhaps tie a bit more into each other.
In general, military applied science spin of from more general civilisation spanning science... so engine technology, power generation etc should be a civilian basic science that you later can do military application of requiring more sophisticated research and higher level of costs and specialisation. Civilian research does not exclusively mean private research... it would most of the time be government funded research in addition to private industrial research.
I also would like to see civilian technology spread between colonies and not get applied everywhere at the same time. So, whenever something is discovered it start somewhere and then spread through trade and having civilian research facilities on the colonies. Mining colonies would be depending on populated colonies close by to influence them. So remote mining colonies could take some time to get updated mining technologies applied. This would encourage building small populated colonies along your border even more. If not just as administrative outpost to spread technology.
I don't think it need to be very complicated, just that each technology have a separate rating for each colony and the spread to colonies depend on their types, number of population, trade and local research facilities to speed up integration of new civilian technologies.
We then have military research facilities that work exclusively on "military" application of basic research. When you discovered the pre-requisite of a new engine your civilian industry (civilian research complexes) can develop new civilian engines while you need military specific research facilities to research military applications of the same engine types.
Facilities should also be built to service a specific category of research with the ability to convert them to another field the same way you can convert a mine into an auto-mine (more or less).
Military science installation should require much less population but be way more expensive to operate from a wealth perspective and probably also a bit more expensive to build.
I would also like to see that adding more complexes to a single project should have diminishing return for the amount of RP you get. The admin rating could instead impact the penalties for adding more labs to a single project.
With the above rules it would make more sense to spread you civilian research complexes among many colonies but keep your military research more centralised, this makes allot of sense realistically. If you don't have some civilian research in large population centres it will take a very long time for such colonies to adapt to newly discovered efficiency technologies.
I also think that we should be able to set the rate at which technology spread as some people will like it more than others, the same way we can control rate of research and survey speed. So you could set the speed at ten times the normal or perhaps like I probably would reduce it quite significantly so it is a real problem I need to actual deal and account for when setting up colonies and mining operations.