I've said this many times but I will rehash again here...

I think the specializations need to be truely special and unique and lock out the other options. 
In the Engine research tree each time one gets a new engine type there is the option for specialization of Smaller/Faster/cheaper     so just because you went smaller the first time doesn't mean you can't chose faster the next time or cheaper the time after that...

I think that in the current build the speicalizations were mostly put in to slow the research path down as "speed bumps"  rather than actually make them as specializations that significanly adjust the game play.

I think there should only be one... or perhaps two points of specialization per tree.     these should lock out the other options.  However I think once they are chosen it should give options for some unique technologies that are ONLY down that specialization tree...

so say you chose smaller weapons.   perhaps this opens up a path where you can then research anti-fighter pods for your ships...   or better fighter weapons specifically for your fighters.

Say you went down the faster engine path...  perhaps this should open up an option to have hyper-super-folder engines late in the game...

Say you chose research focus? Perhaps this opens up an industrial building that gives adjacency bonuses to both industry and tech...

Say you chose to specialize in aquatic worlds...  this should give you some buildings that can ONLY be built on aquatic worlds to better use those worlds..


By moving WHEN and where in the tree a specialization path is available  SD could further change the way the races play... Dregin specialize in military very early...      The Altarians might not specialize in it at all... etc

Beyond that I think there are a few techs in general that should be added:

Antifighter weapons... either via a module or as stand alone weapons.

A special module that lets ships target multiple ships at once rather than all on one fireing.

Cloaking technology that lets you hide from sensors unless you are within x number of hexes (this could be a whole branch down the sensor tech tree)

Sensor jamming that blocks sensors...  again unless you are within x many hexes of the source  (perhaps put this on military starbases to make them worth building?)

Thrusters that actually do something




This is by no means an exhaustive list....     feel free to add to my suggestions.