I like the "get XX kills in a country's aircraft" theme, it's good... but... if anything you highlighted (for me) how these are gonna kinda be (one of hopefuly soon to be very many) bland/common/average/typical achievements about to get introduced. Imho I think the ones where you score more kills in a ride than the highest scoring and recorded ace are gonna be the funner/better ones. With those, each individual one will be unique and challenging and different.