Crisp? That could be Primes territory, but the good zooms are very close. With birding, you cannot have too much reach, at 300mm, you'll probably be found wanting more. Nice opening shots btw. Welcome along..
The nice thing about that D3300 is that it has an APS-C sensor... When you use a 300mm tele zoom, you're really getting the equivalent of a 450mm zoom. It makes bird 'hunting' that much more fun from further away. Check up on APS-C conversion factors for lenses if you haven't done that bit already.