On the plus side, you have a larger capacity battery. Your MBP requires an 85W charger, and the MBA uses a 45W charger. So that's indicative of power consumption. Apple advertised the 2014 MBP at 8 hours of wireless web usage; the 2017 MBA is rated at 12 hours. So you should see 1.5x on the MBA.
mAh does not make much sense in battery spec sheets. Capacity of the battery also depends on nominal voltage. LiPO nominal voltage is 3.7V. Assuming MacBook Pro battery would have that, 3 x 3.7 x 5.152 = 57 Wh. Which is close. Internally three batteries are more likely connected in series. Thus still being 5152mAh, but having nominal voltage of41,838 points. That is a great battery, as it should be so new. Time to get to full charge depends on the depth of discharge, so if you do not discharge very far, an hour and a half is good. Some will vary over time, as will the capacity from day-to-day so I would not worry about that too much. There is a good article in Battery University
MacBook Air 13 inch A1369 models made in Mid 2011 to Mid 2015 MacBook Air 13" 1.7 GHz MacBook Air 13" 1.8 GHz MacBook Air 13" A1466 Mid 2012 MacBook Air 13" 1.8 GHz i5 Processor Mid 2012 MacBook Air 13" 2.0 GHz i7 Processor Mid 2012 MD231LL/A . 161 178 224 223 23 183 38 197