I can't stand barking dogs, that bark for no cause.
The mrs terrier, barks at every noise, every car etc etc.
My gang are silent, right until it's something 'not right', i.e anyone in the yard once we have gone up to bed, or anyone who isn't me approaching the kennel doors, or round the vehicles etc. Then they go crazy and I know 100% if they start barking at night, to jump out of bed very quick. So far they have never been wrong! But when told to shut up, they do so.
As for the nipping, it sounds like the dog is under socialised, and quite possibly slightly under stimulated. Dogs are naturally orally fixated, and all of mine have been in particular. Some breeds are more so than others - i.e spaniels, land, terriers, lurchers etc, or at least have been in my experience. My solution is not to indulge it, i.e as soon as they start to bite / nip hands etc, they are corrected, not nastily, but firmly, and put in their place. They are then distracted, in some cases, with a 'tug' toy, usually just a rag or something, but always the same thing, it allows them to vent some of their drive and excitement in a constructive manner (obviously i never do this with gun dogs!).
In general though, you should be top dog, and if you say, stop, leave or no, or just tell the dog to stick with you, then it should do so!
Mind you, having said that, some collies are just biters, our farm collie has had two people, who thought it wise to explore the quad shed while she (but not us) were in the yard. Obviously once bitten, they were 'just looking'. . . .