The VOIDRUNNER'S CODEX is coming! Explore new worlds, fight oppressive empires, fend off fearsome aliens, and wield deadly psionics with this comprehensive boxed set expansion for 5E and A5E!
ECL and CR have nothing to do with each other. ECL is a measure of how likely a creature is to grab the limelight as a PC. CR is a measure of how tough it is for a party to kill.
A lizardfolk ari1 would have a CR of 1, as I recall.
ECL and CR are completely seperate. Even though he has a +4 ECL, a Lizardfolk still has a CR of 1. The PC's CR is 1 (actually 1.5). NPC classes add 1/2 CR per level, which is rounded down.