Hmm... not my experience. Not discounting yours at all, I promise, but I have a 20-package one-liner install script that I run on new systems and it's ready to go. After I pull in my dotfiles and symlink them into place, I can't even tell it's a different install.
Arch is pretty much exactly as opinionated as I want a distro to be. Hell, there are LOTS of folks who think it's too opinionated for forcing you to use systemd. The real installer is pacstrap, and it installs, I think, 300+ megs of stuff. That's all someone's opinion. And keeping it to just 300 megs is an opinion too, I guess.
EDIT: Okay, re-reading, and it sounds like installing 20 packages is a pain. But when I used Ubuntu I had to go through way more to get it how I liked it (and OS X is a nightmare 2 hours of clicking menus and buttons, and installing from web pages). I don't remember all of it now, but I had to get rid of the weird mini-vim and replace it with neovim, strip out Libre Office (nothing against them, I just have no use and it's a pain to wait for the giant updates all the time), my printer drivers were on a webpage somewhere, not the repo like Arch, etc. Ubuntu is WAY more work for me to get set up with just because removing and replacing is more work than installing.