Hi Wyl!
The "dunkel blau" one is for the 3thd.GUR during the 1900's and the "feldgrau" one is for the UR.15 - 3.Esk in 1916. The two first tschapkas are both from the GUR.3 during the 1870's and the 1880's, one is a personnal purchase model with its yellow Rabatte and the second one is a typical line model 1867 for EM.
The two others are correct with the AKO of september 1915 for the three Garde Ulanen Regiments, one is completely made with leather and the second one has a typical removable tin upper top. Be patient, Wyl, I'll soon send to the forum a picture of my entire collection... I'm just waiting the last items that would complete it.