If the wallplate locations are assumed to be at a gear location and behind a TV, I would generally recommend running a direct single cable run through a hole plate rather than using an HDMI coupler plate. It would be behind the TV and behind a gear location anyway, so having a coupler plate really is kind of pointless, and if the run is long and you're at the edge of the cliff having two extra junction points could push you over. I would generally just avoid it given how many HDMI failures I've seen.
As far as cabling over distance, depends how accessible the run is. If it's possible you could re-pull another wire later, I might cheap out and get a monoprice HDMi cable. If not, I would go for peace of mind and get the very best HDMI cable bar none which is the belden cable sold by bluejeans.com.
However, I also would ABSOLUTELY pull a minimum of two cat6 runs along with the HDMI for future proofing, and also as plan B so you could use HDMI baluns if you need to.