I'm not sure how it took 17 years to realize this obvious need (perhaps even the most basic one!).
I think it's simply silly that Windows users can just download new software, while Linux users doing distribution updates (which is what they are supposed to do) have to wait up to 6 months for new software.
The solution is simple: try to trust upstreams.
If upstream releases a new stable version, then assume it's a _stable_ version and thus _immediately_ include it as an update to the stable distribution.
If any upstream is caught releasing "stable" releases that are not suitable for being updates to stable distributions, then _complain_ to upstream loudly, _help_ them get better QA polices, and delay their updates as is done now until the process issues are fixed.
For security updates, it's also simple: just use the update provided by the upstream.
If upstream refuses to release a stable version with the security update, complain, help and delay updates as above.
In other words, just stop attempting to duplicate stabilization work in every distro by forking all packages, and instead tell the problems upstream and help them make better releases.