Actually if you ask me, Aakesh was never interested in interfering with the naag clan. It was his father that was after the naag mani and ordered his henchmen to go after them. Aakesh was only interested in Naageshwari and the reason why he killed the other naags was because they were getting in the way plus it was his nature back then given their enmity with each other. But after falling for Nageshvari and dying at her hands the change began and probably got carried forward to his present life without him realizing it.
Exactly! His dad who is head of cheel clan was the one who saw naagvansh as enemy of cheel. Aakesh on the other hand wasn't shown to have any ill-feelings towards naagvansh, and he was shown as more cunning and a trickster rather than ruthless.