Would be nice to be able to use both together and be officially supported by OpenXCom team.
Both shoes and yankes could continue working on their mods and have any new features or changes be patches authored by lead devs.
I'm thinking perhaps after OpenXCom 2.0 and once both support TFTD cause I think atm only xcom1 is supported. Both mods are quite mature and stable and would be a great addition to the engine as a whole.
Stat tracking code + interface enhancements can be included into main branch and have Commendations as a separate optional downloadable mod.
Extended is essentially the next up engine after xcom1/xcom2. I would say if there was an xcom3 it would probably have had Extended like engine enhancements. Just like TFTD made some changes to UFO, Extended made some changes to TFTD/UFO. Since extended makes some gameplay changes maybe have them default to xcom1/xcom2 behaviour and use rulesets to tap into the engine enhancements.
Probably somtimes after 2.0 is released all devs could sit down and have a talk grab useful features from both of these mods and include it into main branch.
Combining both of these would probably yield an instant OpenXCom 3.0.
What do you guys think?