This 16 segment limit raises the value of A/DONE3 quite a lot (compared to 4-6 continent ITNs, that is). From NA-EUR-ASIA ticket you'll still get out quite a lot, nearly the max. available.
On the other hand, especially for A/DONE5/6 I see very little value/use in the future. I think any LONEx is still good for those who are able to suffer it through in the first place..