Two Problems with using Brother printer HL-L2350DW

According to Brother, this printer should be able to function thru AirPrint without installation of drivers. It does print, but I'm experiencing two problems that the Brother Chat doesn't know how to fix.

(i) Even though I set the Brother as my Default, AirPrint constantly acts as if my older HP printer is the default, as it previously was. (I still keep the HP available as my scanner since the Brother is only a laser printer.)

(ii) The printing is very dark. This is fine for text, but the images are coming out very poorly because everything is so dark, losing any distinction. This is true whether it's in Draft, Normal, or Best. Not only that, but Brother says I should have a wider variety of menu choices than it looks like is coming up with AirPrint (see attached screen shot). Is there no further control of darkness than this?

Thank you. xo