I’m talking about all live opponents not weak ones.  The examples I gave were meant to be more black and white, but everyone has a playstyle and preferences, and limitations.  They can tell me about their preferences in words, or I can just play with them often enough to see how they operate.
The Professor tends to like bold attacks and so he’s beaten me by taking Iwo and when the tables were turned, Hawaii.  That means that he likes to do one big attack and not dilute that with picking off the small stuff at the edges, which means the mice eventually eat his empire…
The Realtor likes to have a bunch of small navies all over the board, so that there are many targets that you cant kill, and he is around every corner.  He’s good as the UK, but he leaves too many ships where you can pick them off.  He intercepts every time he can.
The Postman is good at reacting, so surprising him probably isn’t going to work.  His proactive strategy isn’t as strong.
Maphead misses nothing, uses his planes like a lightsaber.  He used to be my student, since I can’t really figure out how to beat him, I usually try to get on his team so I don’t have to.
Knowing your opponent is key to victory.  Winning isn’t everything; but everything you need to win isn’t always on the board.