I've found that the way colonisation works now makes AI nations wanting to compete to the point of being entirely nonsenical. One can easily utilize this to further one's own goals. When I colonized Africa as Germany, I was a latecomer as I had no good naval technology and no high-level ports. So in 1870, I first had to justify war against one of the African countries, conquered part of them, and then started wildly colonizing. Not only did the AI get into squabbles with each other, ignoring the lands that were just there for the taking, but I could also strategically use it to keep them away from certain territory - I competed with the Ottomans and France over one territory just to keep them bound there.
Other than that, games aren't predictable. Just because in your game, the UK is shoving you around doesn't mean it has to happen every game. When I played the US, I instantly got the colony game right (build ships, colonize BC, oppose the Mexicans, use free points as they come along). Then I pissed off all the GPs with the "let's turn Cuba to a slave state" decision, and they ganged up on me in the crisis over BC, and the only result was them getting the territory, which isn't too terrible. The Brits, like everyone, hated me at this point and I barely had an army. But then, a lot of crises happened, and in every single one the UK were on the losing side, to the point of France getting to first place (and Russia occupying Greece). As the US, you have little reason to whine about the crisis system: the only GP that can keep their head out even further is Japan. If you were in continental Europe, you'd constantly have to pick sides or lose prestige, and it's much riskier. And in the end, if you want someone to stay off your back, just improve your relations with them. As the US, you usually will want good relations with the UK, which is basically the only Great Power with any real possibilities and motives to tear you a new one.