Very nice change, I like it.
But there is one thing that I think needs attention.
I'm doing it from memory, so please excuse inaccuracies, but with those stats the CEB (I'll just call them that in short) will have 200 atk and 200 def whenever PDCs are involved, for a meager 180 training points. Doesn't this render most other troop types obsolete, especially when defending?
I usually have at least one division worth of ground troops in PDCs on every population center, and with this change I'd load it up with nothing but CEBs (plus their headquarters, of course), which seems strange to me.
I think a change to something like 90 atk 90 def would be better, and instead of doubling their own strength make them give a non-stackable bonus to every other unit stationed in the same PDC / to every other unit attacking the same PDC.
That way you'd rather fill your brigade sized PDC barracks with 1xBHQ, 1xCEB and 3 other units, instead of 1xBHQ and 4xCEB.
any chance of some new ground units ?
Maybe Light Infantry or Super Heavy Armour (Battlemechs/OGRES) 
Something I'd like to add to this, because that occurred to me before and it seems fitting here.
How about hindring ground troops if they are fighting in an environment that is hostile to your race. (the higher the colony cost on a surface would be for your race, the less able your troops are to fight in that environment) Worst case, for a world that is deemed unfitting and/or has a cost over 10 your troops are reduced to 20% of their abilities.
Introducing XET, Xeno Environment Troops (size 5, 50 atk, 100 def and 120 training points), basically a normal INF that is trained and outfitted to deal with those worlds. Marines are also fine in such situations (being trained for space combat, which usually is a very hostile environment
), but more expensive.
