Skype works fine if you use pulseaudio (no more alsa support). It's in AUR: https://aur.archlinux.org/packages/skype/
But nowadays if I'm forced to use Skype (I use Hangouts for everything) then I simply go to https://web.skype.com/
Steam also works fine. It's actually a package in multilib repo: https://www.archlinux.org/packages/multilib/x86_64/steam/
Sometimes there are some glitches, but wiki page on fixing issues is a great resource: https://wiki.archlinux.org/index.php/Steam/Troubleshooting
I actually run two Steam instances - one native on Arch, one through wine
for Windows games. Both steam's work fine.
Other 3rd party binary-only software I run on Arch:
* IDA Pro
* Android Studio
* Android SDK & NDK
* Google Chrome
* Plex Media Server
* Sublime Text v3
* BitTorrent Sync (now called Resilio Sync)
All the updates for 3rd party software are very automatic if they are available in AUR. Just use AUR helper like pacaur instead of default pacman.
As usual with Linux, sometimes there is something that doesn't work out of box. Then you really need to open terminal and fix things, you cannot avoid that on Arch. If you use Arch then you must not be afraid of terminal.