Lycan's nerf was purely to his wolves and his ability to jungle and farm efficiently. It was a clever nerf.
Naga siren on the other hand got destroyed
except naga was picked and banned quite a bit at ti3 while lycan was picked and banned 0 times? hmmm
The reversion on the riptide nerf was nice, but I think support naga would have functioned regardless. Lycan's +armor buffs didn't get him recognized.