Thanks for your input, I´ll certainly use some of it for the next games. The scenario-setup was that limited simply because I´ve not yet painted enough minis to field a larger formation

So, we started nice and slow with a very limited engagement. It was intended to keep the number of enemies low as well (3 Groups + Mortar team in the beginning, nothing overwhelming) but the reinforcements just kept coming...
Regarding the actual game, I think you are quite right with point 6 which confirms my assessment, that the major mistake was moving Team Blue forward while Green kept getting punished, thus separating the elements and making them more vulnerable. Of course I then ordered all Taliban to increase pressure on the already hampered team.