I grew up on Gundam Wing. It’s quite the ride now that I’m older and see a lot of the politics at play. And in much the same vein I loved Gundam 00.

But Iron-Blooded Orphans might be the best/most accessible series in the franchise.

Witch from Mercury hits hard at the end of the first season which is a good thing and a staple of the franchise.

Unicorn is bright and shiny. I watched it twice and that’s all I can remember.

Gundam 0080: War in the Pocket is probably the most succinct and existential series with 6 episodes and a build up to reveal how fucking horrible war is.

I dunno, you kind of just gotta jump in and get dirty. The themes vary from series to series but the main timeline, called Universal Century (UC.) is almost always focused on the human aspect.

Gundam is about space battles and politics and giant robots… Until it is about the stress and rigors of war. Not sleeping because you see the people you’ve killed. Overcoming the horror of losing friends, mentors, and loved ones to the fighting.

But again there are a bunch of series, each one is basically it’s own self contained narrative that requires little in the way of prior knowledge. If you see something that interests you just jump in and watch it. I’m currently gearing up to watch the second Gundam Thunderbolt movie. The first one was pretty damn intense and I needed a three week cool down period.

On a more general anime note, I highly recommend the Apothecary Diaries.