Socialism gives the benefits of capitalism but reduces the bad stuff. I love socialism.
Maybe you should pay a visit to Sweden then. Horribly inefficient, bloated public sector and the world's second highest tax, yet no better than many far less taxed countries. We used to have fantastic growth and development, but as socialism took root from the 50s to the 70s, everything slowed down to a crawl. The only thing keeping us afloat is our world class private sector.
So too much socialism is definitely not a nice thing.
It's not really a "this is good, that is bad" thing with politics. If it were that easy, we wouldn't have all this stuff with ideologies. Socialism is generally a neat balance.
Capitalism messes up horribly in things where money can't help - it takes money to make money, and people who don't have money are messed up by capitalism. Communism messes up because you fail to reward people properly. It also appeals to natural forces (contentment of the masses) just as capitalism appeals to a natural force (greed). Both, when firmly rooted into an economy, are hard to change.
Socialism rewards hardworking people, takes money from those who have the means to support others, and give it to the needy so that they can work hard, get more money, and become taxable. It's nice in that it allows people to get ahead in life by working hard, and nice that it gives everyone a chance. It gives everyone equal opportunity if done right.
Socialism can fail utterly when you misdefine who has the means and how much others need. Take too much from the rich and you make it difficult for them to become richer, hence your case with Sweden. Moderate taxes work.