Once they reach the experienced needed to promote to Advanced, I then want to have them "upgrade" to finish the process. Basically Merc dont recieved techs from forrge/wtf etc... they also dont rank up like regular "CS"  they are gready MFs!  They want more "gold" to fight harder

This is already possible, isn't? Can be done with characters like =P

You want it to promote upon upgrading? Or do you want the user to have the choice of upgrading by spending some metal vs promoting by letting the unit gain xp. If it is the latter, yes this should work.

Want to try something new with Merc in Classical Warfare AEA.  I havent tried yet, cause I figuted I would ask before nubbing and creating errors.  Can I write it so the Promotion is includeded in the upgrade?    <Upgrade>     <veteran>       <Entity>units/athen/merc_inf_archer_market_a</Entity>       <Tooltip>Rank up to veteran status.</Tooltip>       <Cost>         <metal>10</metal>       </Cost>       <Variant>upgrading</Variant>       <Time>10</Time>     </veteran>   </Upgrade>   <Promotion>     <Entity>units/athen/merc_inf_archer_market_a</Entity>   </Promotion>

Tiny precision, I wasn't trying to blame the process  I saw how it works well to generate hardened quality code, the time reviewer spend to read your (sometimes sh!ty) code is never to be taken granted --thanks by the way @Vantha, @phosit, @Stan` for the reviews on my PRs --. But simply the additional time to be spent on trying to get any feature into the game (again the 1-2 order of magnitude larger of work isn't a exaggeration, add to this waiting time) create a very real limit to what you can get done, even over a large time frame. Your suggestions to try to organize the collaboration although nice, can hardly solve this dilemma.