If you're wishing to use a soundbar, the simplest option would be to use a soundbar with built in HDMI with inputs and outputs.
Yamaha offer the YSP-1600 which has ARC together with an extra HDMI input which means you can uses. This means you can use one of your TV's HDMI inputs plus one of the Yamaha's plus the ARC HDMI giving you the required inputs plus a half decent sound bar