Quick update --
We're preparing a hotfix to go live soon which will widen the power gap a bit between players between 110 to 120. This means that, for example, a 120 will be stronger against a 115 after the hotfix than they are on live today.
Regarding lower level players being stronger at a lower level than they would be at max level, we haven't found that to be the case. (Though to be fair, that was regretfully the case in some situations in beta and on live because of bugs.)
In the case of Venruki, we loaded both characters internally and tested the scenario (exact spell sequences, etc.) with his Druid opponent at max level with gear the same iLevel as his Mage. Venruki would still of lost in that scenario if the Druid was at the same level and iLevel as him, so it is not a scaling issue between players of different levels but perhaps something else (1v1 class balance, item choices, etc.).
Actually, the PvP scaling changes are now live. We'll continue to monitor things and make changes where necessary. Thanks everyone.