Netgear EX7000 signal strength/ antenna dbi ?

I recieved my EX7000 and connected as an access point -so that it provides wifi for the two floors in my apartment (replacing my Asus RT-AC66U -which was also setup as an access point) -I purchased the EX7000 for its 700wm signal power output -as well as its high speeds.
Using Netgear's Wifi Analyser App I went around my apartment checking the signal strength in several areas and would like to check with other users out there the kind of values that they would expect.

Note: the channels are clear 

2.4Ghz:
  0m/0ft: -17dBm (on top of EX7000)
  2m/6ft: -40dBm (line of sight)
  3m/12ft: -45dbm (adjacent room - through hollow wall)
  5m/15ft: -65dBm (downstairs - through concreate floor)

5Ghz
  0m/0ft: -17dBm (on top of EX7000)
  2m/6ft: -40dBm (line of sight)
  3m/12ft: -50dbm (adjacent room - through hollow wall)
  5m/15ft: -75dBm (downstairs - through concreate floor)

Do these values look typical ? as I am only seeing a slight increase in dBm (2 or 3 dBm) compared to that of the Asus -to be honest I thought that the extra power 700mw compare to that of the Asus's <180mw would of boosted it big time!

Also, what are the EX7000 antenna's dBi rated at? -as I am considering on of getting some with a higher gain.

I would appreciate any insight

Cheers

(btw: I am aware that 5ghz range is shorter than that of 2.4Ghz -as well as a wifi's typical donnut style signal dispersion)