I'm relatively new at high level gunboats, so I'm not the best person to answer, and I don't recommend me as a role model, because quite frankly, I rarely ever win them. But I like the thread and would like to get it started. The underlying assumption in what I write is that I almost only play WTA, and when I don't, I play it like a WTA game anyway.
In gunboats, even more than in press games, I spend a lot of time looking at the balance of the board. Since there's no communication to warn about a solo threat, one needs to be even more proactive. If I see someone edging close to the stalemate line, with a very good position to get past it in one or two years, I divert most of my efforts to fighting this person. Maybe this is why I rarely win, and draw so much. Unless I'm the first to reach a dominant position, I don't go for my own solo if there is a risk it will grant someone else the win. I'd love to hear what people like Barn3tt have to say, those who truly excel at gunboats.