Software development on anything more than a pet projects is a collaborative activity. To enable a group of developers to make any headway, some details inevitably need to be hammered out together. However, you probably find that getting agreement within a group of opinionated developers can be difficult at the best of times. Most software developers haven't had training in "soft skills" and you may find it hard to know where to start when a difficult question needs to be thrashed out.
Here are some pointers to areas that you might want to explore beyond the realm of programming languages, methods and frameworks.
Facilitation is all about making conversations easier but even with a clear meeting purpose and agenda, you may find meetings can go around in circles without reaching consensus. To understand some approaches to making group decisions I recommend "Facilitator's Guide to Participatory Decision-Making" which introduces decision making rules. You can also get affordable hands-on training in facilitation from non-profit ICA-UK on Group Facilitation Methods.
Another thing you can do to help meeting participants is to create visible agendas and capture points being discussed concisely. If you want to build more confidence with writing neatly on flipcharts and whiteboards, seek out a course in graphic facilitation where you can pick up tips and practice with other budding facilitators. To improve how you illustrate system dynamics in group discussions, start to practice drawing Diagrams of Effects. Peter Senge's book "The Fifth Discipline" has a an excellent introduction to Systems Thinking and an handy set of system archetypes that you can use in different situations.
There's an old joke: What is the difference between a Methodologist and a Terrorist? You can negotiate with a terrorist! When discussions get heated, it's handy to know a little bit about negotiation techniques. The Harvard Negotiation Project have put out a few paperbacks and I recommend "Getting Past No: Negotiating With Difficult People" by Fisher and Ury. Another easy read around building trust is "The Trusted Advisor" by Maister, Green and Galford.
Lastly remember that we can improve communication in our teams by starting with ourselves and how we express our own opinions. A good place to start is "Nonviolent Communication" by Marshall Rosenberg. An older book that's worth getting hold of to get a different perspective on the way you share feedback is "The Art of Giving Feedback" by Charles Seashore and Gerald Weinberg.
I hope these resources help you in situations where you need to go outside your comfort zone. Please do let me know if you have other recommended reading to share that goes beyond coding.