Hellenistic Era arms

Nov 2013
How would you rate Greek martial performance in the Hellenistic era? It seems to have declined....except the Hellenistic world was so large, maybe it was actually fine, somewhere.

How about the Greco-Bactrian kingdoms? Greeks seem to last a while there, was it due to martial talents, or simply because the ruling class there was not as Greek as the ruling class in Egypt?
Apr 2018
It does not seems that the Greco-Bactrian kingdom was luckier then the Ptolemaic Kingdom. This last was quite able to mortally weaken the Seleucid Empire, and this gave to the Greco-Bactrian kingdom the possibility to born. But, after this, the Greco-Bactrian kingdom was defeted by the Parthians and finally destructed by several invasions around 125/120BC, while the Ptolemaic Kingdom was finally defeated only in the 30BC.