I have been testing using unicorn for site content and TDS, in a Helix format, for templates/layouts/etc.... It reduces the merge conflicts a lot. Unicorn for content because content is changing A LOT in dev. And Helix so I don't have 10 developers in 1 TDS project. I have 35 TDS projects with a minimal number of developers and conflicts.
Making my life a lot easier.
Do have to remember to sync TDS before unicorn because the templates that unicorn needs are in TDS.
How to do it
You can install unicorn into your solution via Nuget.
Install-Package Unicorn -Version 3.3.2
This will install the dlls and some sample configs. What you want is a unicorn serialization config that only does content. I great example of that is the official habitat solution. For each project in Helix you will have a config that deals with just content. For Habitat that config is Habitat.Website.Serialization.config.
This is an example of that config. What you want is for unicorn to keep track of the site content and media. This will make it so any developer who adds, removes or updates content in the dev solution, will automatically get that updated in source control. This make merging content very easy.
<configuration name="Project.Habitat.Website" description="Habitat content" >
<targetDataStore physicalRootPath="$(sourceFolder)\project\habitat\serialization" type="Rainbow.Storage.SerializationFileSystemDataStore, Rainbow" useDataCache="false" singleInstance="true" />
<predicate type="Unicorn.Predicates.SerializationPresetPredicate, Unicorn" singleInstance="true">
<include name="Habitat.Website.Content" database="master" path="/sitecore/content/Habitat" />
<include name="Habitat.Website.Media" database="master" path="/sitecore/media library/Habitat" />
You an find more info on unicorn is here
For TDS and Helix, lucky for us Hedgehog has taken the Helix solution and TDS'ified it. You can find that branch in Hedgehogs Helix fork.
Specifially, looking at this link, you can see how TDS is used in a feature in Helix. Each feature, foundation and project project gets its own TDS project in a folder called tds. The only thing that the tds project would track is just the templates, layouts, renderings, etc... for this feature. This limits the number of developers who would be updating this single TDS project.
To deploy all the projects, I am using a platform TDS project that uses the package bundling feature of TDS to bring all the TDS projects together into one single .update file that you can send to production.