Excellent shot. Do you find the EM1.3 faster or more accurate to focus than the EM1.2 with native and/or adapted lenses?
EM1.3 has better color science thats for sure as i get true white's in AWB compare to all other Oly bodies include the EM1X.
About the C-AF its a marginal diff between 1.2 and 1.3 which Personally i would not consider an option to upgrade but yes i did upgraded to em1.3 and i do have em1.2 as well.
Adapted lenses i have used canon 500 and 600 with / without tc and I have found that i am liking its rendering because i can get 2x crop already while taking images . It has its own con's like AF one has to work only S-af and that too on limit as you can not get action unless you have steady hands and bigger bird to catch in flight or a slow moving bird can be achieved like cranes / pelicans / partially bigger eagles in soaring mode or some bigger ducks or owls but song birds or mamals in rapid or erratic movement action will be a miss in s-af.
I have been testing the native 300 with em1x this days on local bird sanctuary lake but in our part of world bird photography is not that easy and one has to fight with distance shots .. Plus heat in atmosphere very early in day and stay till evening .
My general evaluation for myself or my own experience if the bird is in a descent range s-af gives super results with native lens like 300/f4 .. c-af is a 50-50 chance as in limited low burst 2-3/10 frames can be usable having fine feather and bit of processing is also required.
Hope this helps.