[Strike Witch]

But what's the fun of watching a show where all the protagonists are like invincible

Usually, about half of the protagonist cast in a Gundam show die. It depends of the show, of course. Concerning main characters, one has died outright, one was level brain-damaged, one maimed, and one was absorbed by an alien ai thingy.

Not to mention the fact that it's kind of hard identify with characters that look like ten year olds with huge purple eyes

Actually, most of them have smaller eyes then you're thinking. the majority colour is brown. Also they come in several age groups, not ten year olds.

"War drama" lulz

Even at it's worst, it's still much better than "An alien robot crab ate an ancient civilization and here shoot at this hopper palette swap while we kill it out the window".