I've been feeding raw for about 10 years now and totally love it. I've used Primal, Natures Variety, Artisan, Stellas and more.
Right now I'm using
Sojo's - and really LOVE it! You just add your own meat and water - the rest is nutritionally balanced.
Your vet is 100% -- what you're currently giving is NOT balanced at all - and you need to rectify that quickly - especially bc your kiddos are so young and still developing.
There is also prey-model raw diet as well.