Yes, Socialism and Totalitarianism are definitely strong, but I tried to make the alternatives to them viable as well.
Capitalism is a more idle and relaxed version of Socialist growth - if you get a money symbol on all sides, you can stop worrying about having hammers. Feudalism also does not require you to recycle population constantly, but it does require to keep it employed in Farms. I guess those alternatives are worse because they are only linear, though.
While Totalitarianism is great at reducing the influence gain, once you achieve that, you can explore other options. Democracy provides the only way to get the government symbol on a die, while Autocracy lets you get symbols into strange places and opens up options in there.
Social systems are indeed not really important. Caste System is great but hurts you at one specific point in the game, and Egalitarianism can be situationally useful, but they are not as strong as the other categories.