A lot to tackle here but I'l address a few things.
Characters: pretty much a complaint of everyone and one of the real downfalls of the game as they weren't nearly as strong as the original trilogy. At this point you should be able to romance any character.
Tempest: while I agree customization would be nice, given it's strictly an explorer ship with no weapons and you don't control it outside the galaxy map, upgrades are kinda pointless. I would like to see a lot more done with controlling the ship though but that's been the case since the original. Also, the Tempest is smaller than even the original Normandy and is meant for exploration. It makes sense a small exploration ship has far less crew than a warship.
Nomad: yeah, half the mods were worthless and I wish it had weapons and a turret like the Mako did.
Armors: I agree there needs to be more and they need to drop inherent traits; just let them be aesthetic parts and add the mods as you see fit. ME2 did have the bet aesthetic customization and about the only RPG feature the game got right. I disagree with the Deep Space Explorer armor; once I got high enough level/research I dumped it for the Hyperguardian and never went back.
Weapons: I was fine with customizations for the most part but more wouldn't hurt. They definitely need to add aesthetic customization for them though.
I didn't think item costs were bad at all. They may be hard to scrounge up at the start but that's any RPG.
Ryder customization was definitely subpar, and I don't know why there were so few choices for outfits. And yes, the hair choices were bad.
Drack looked fine to me.
I believe there were kids but they were unfreezing people based on necessity/priority. Kids who just take up resources, which are scarce when starting, are going to be low on that list.
I don't think there will be anymore content for ME:A aside maybe a remastered edition for next gen, but even then it would just be better graphics and no new content. EA abandoned the game way too fast after they severely hampered it's development.
