I think it depends on your play style. I like to turtle and entrenchment is a defensive expansion so I am having a blast with it. If you are more aggressive it will still be a big improvement but you may just want to wait untill another expansion comes out.  I have noticed that the enemy retreats a lot less in entrenchment (but that may have changed in the original (vanilla?) at the same time.

No they don't retreat a lot less in vinalla now, I come in with a fleet of ship, the enemy AI on normal was twice my size and they still retreat upon entering the system.

One of the major reason i got Entrenchment so I could get starbases, and for a Trekker, the original star trek mod is not longer develop so, I got entrenchment to hopefully continue to play it

Thanks guys it sounds like this is worth the only 10 bucks it takes to get. Are there anymore new ships though? I heard of starbases and defences but what about new Cap ships and Frigetes.