Dex 13 base + 2 tome + 6 item + 1+2 exceptional (gilvenor's ring?) = 24
to-hit:
15 BAB
5 divine power
3 divine favor
7 dex
4 crafted on rune arm
4 greater heroism
5 tharne's goggles
1 enhancement
7 weapon (5 plus 2 battle engineer)
1 point-blank shot
1 haste
=53
Some AC benchmarks,
Also note that your artificer's dog, who contributes near-negligible dps at endgame, can happily wield a Maladroit of Improved Destruction module and drastically drop enemy AC.