I see
@GIGGIRIVA point that no one wants to work on something they are not interested in and it's fair.
Independent addons obviously can be developed, but the main issue I see is integration with CP IDs.
Let's say I created 2010-2019 teams with all kits, stadiums, balls, adboards etc and when new CP Clubs gets released, all those IDs are taken by e.g. Conmebol 2000-05, that means weeks and months of reassigning and reimporting all I have done.
And then after all that Unica comes out and it's all undone once again.
What I propose is some sort of coordination with DB and IDs.
Let's say
@acicog30 & team finished up on UEFA 2005-10 DB, so he announces that the last team ID used is 111222 & last stadium ID is 333 and proceedes to assign graphics etc. The DB is shared privately (e.g. with me) and we (the 2010+) team start working on 2010-15, stating that we will need IDs from 111223 to 111555 and stadium IDs from 333 to 400.
This is the rough idea of having synergy and non-conflicting IDs.