Boars are instant reaggro. Freetaming boars last world took me less then 10 min to taim. The issue is that damn long taming cooldown. If a alt jumped me with combat med before I did that last taming move it did reduce it to some reasonable cooldown.
And as stated above. Cows / Sheep can be tamed fairly quickly using the trick where you deaggro the herd and reaggro on any herd member except the one your trying to taim.