As a general rule, players with higher salaries are better than players with lower salaries. It's not exact, because players with lower salaries could be getting trained, and their salary increase won't happen until the end of the season. Also, some players have higher salary simply because they're high in one skill, and low in others. Often, a lower salary player with balanced skills will be better than a higher salary player with one awesome skill.
But in general, and in your case I think, those teams can't hang with you (although I do recommend getting a few more players to help with minutes distribution and game shape).
Country and World Rankings are wildly inconsistent, and really shouldn't be used as a bearing on who is better than whom. Especially for newer teams.