Three characters, .org, X-for-Y. O4A reads as opportunity for all, organisations for action, or outcomes for all.
Opportunity for all is close to a universal mission statement in the social sector, used by education charities, employment programmes, and equity initiatives across every market. A name that states it in three characters is unusually efficient for an organisation that has to put its identity on grant applications, annual reports, and partner materials constantly.
The for-all construction in particular carries weight. It signals universality, which is the framing most social programmes want, and it does it without a word of explanation.
Three characters also means nobody shortens it for you. Organisations with long names always end up with an abbreviation somebody else invented, usually an awkward one. Starting short removes that problem permanently.
The name is available. Enquiries welcome.