Snake Charm is a niche spell, it has its uses but is usually not all that useful, unless you are fighting a lot of snakes. In Dark Queen of Krynn it is very useful in Naulidis, and has no use elsewhere. I do like the lack of target saving throw. You have to prepare a slot for it ahead of time, and you may not need it. You may actually need Hold Person instead.
A Wand of Snake Charm would enable you to have it without losing spell slots.