What I am seeing online is the suggestion that maybe you need to make the query timeout value larger in the agent profile. This plays into the next question that came up. Is this replication across a WAN? Is there slowness in the network between your distributor and the subscribers?

As far as topology suggestions, it might be worth considering setting up a second distribution database for use in one of these publications. See this link about configuring a second distribution database and why you might want to do it.

https://msdn.microsoft.com/en-us/library/ms183524(v=sql.100).aspx

Here is a link to BOL for troubleshooting replication.

https://msdn.microsoft.com/en-us/library/ms151756(v=sql.100).aspx