Broker_XPRate is a LDB plugin designed for the boring times while grinding out the levels. It has two display modes, time to level and kills to level. Both modes take into account the amount of restXP you have if any.
Credit to Laughlorien and KillMeterFu for some of the per kill code
If anyone is willing to help localize this addon, please head over to the localization page and submit translations. I wish I could do it myself, but alas I only know english.
To take advantage of this addon, you need to have a LibDataBroker display addon installed as well.
More information on LibDataBroker can be found on it's wiki
If you feel you have a bug or feature request, please post a ticket on the ticket tracker on Curseforge, a comment on the project is unlikely to get seen in a timely manner.