I'm embedding this very inspiring video of Milton Glaser talking about The Fear Of Failure, because it has so much to do with your own personal development as a leader in your organization. Most team leaders are really leaders because they are very much afraid of failure. They are afraid of what would happen when they take the steps they "dream" about doing for many understandable reasons.
Please watch this video with me.
You can find more of these videos here.
While Milton talks towards designers, who usually need to take risks alone in the beginning, this very much applies to your as a team leader. Your job now is to drive things the way you believe they should be driven. that's a risk, because the second you move a bit away from the norm in your workplace you're going to be tackled with people not liking what you do, and sometimes expressing it very clearly.
You will be on this road pretty much alone in the beginning, charting your own way as a leader. It doesn't mean you shouldn't consult with others, but at the end of the day, leading the team to be more mature than it is can take some personal risk taking. for example, shedding off some commitments so that the team has time to learn, beginning real conversation about reality with management, pushing people to burst out of their bubble - these are all personal risks (that you lose a friend, that you fail at what you do, that people will laugh at you).
Embrace failure, and realize that as long as you keep learning from your mistakes, you can do very little wrong.
Minimizing the risk with experiments
one way to minimize those risks is by declaring "experiments" that last a week or a month. after that you decide what to do next. that way you also limit the risk exposure, but you also get to discover "what if"s that you'd never be able to otherwise. Sometimes doing is the only way of learning. and getting out of the comfort zone for a "timed experiment" is much easier to convince people of than saying "we're doing it this way now".
I'd also venture to say that using an "experiment" is only a temporary technique you should use. at some point you will have to start making permanent changes, at your own risk. Keep that in mind, and watch how many times you try to avoid risk by saying "it's temporary". You will need to decide when it's time to burst your self out of that bubble as well when the time comes.