Some attempts to balance URF
- Champions with shortest cast times (Evelynn, Hecarim) benefit the most from cooldown reduction, because cast times are not reduced by it. So if a spell has e.g. 1s cast time and 1s cooldown, the 80% CDR effectively only grants 40% reduction of the time between spellcasts. Therefore, cast times should also be reduced by 80%.
- Knockups and displacements aren't reduced by the additional tenacity URF provides, so their duration should be reduced accordingly.