Silence, or "dead air" is to be avoided. Dead air can make for awkward moments. You want to be able to connect with your audience.
You want your audience to identify with you. They're either for you or against you. You want the former rather than the latter.
You can reduce delays by having a well-constructed set list that all band members have, either memorized, or written out.
A well-rehearsed band can quickly move to a new song on the spur of the moment, if they are professional enough to not have to fiddle around with their gear in-between songs.
You can also construct medleys of tunes that flow straight from the ending of one tune into the intro of the next tune. This requires lots of rehearsing of outros into intros, round and round, in order to get everyone firing on all cylinders effectively. Once worked out, this is very effective at building momentum.
You can "break the ice" with a short joke or funny comment, but people want to think you're being genuine with them. Be honest, and identify with THEM.
Most of all, have fun, enjoy yourself, and give away your energy. You will most likely receive energy back many times over.
I agree with Bob. It is best if the band can avoid pauses, and move right on to the next song. I like when there are some pauses in between. When you watch band and artists, you'll see that they do it differently. Some like to talk a lot, and some hardly talk at all.
I would put in some talking, because I like to talk and joke, that make me feel more connected to the audience. But it has to feel natural. On my first gig, I said: 'I want everybody to come to the front an LOOK at me'. Hahaha, I meant 'listen', but I guess looking could not be avoided either.
I went to a concert with the Swedish metal band In Flames. They are very professional, but still the vocalist talked so much in between the songs, that I got tired of it. You have to find something that fits your style.
As a performer you need to remember one thing... It's all about the audience. Provide them with an experience and they will come back for more. When practising/rehearsing focus on yourself but once people are listening it's all about them. Any show big or small relate to them in some level and you will stay in business.