I have an overall planned story for my character, part of which runs through the Dark Brotherhood. One of the first sets of contracts you do for them include killing one person that I know starts a small quest (very small in this case). I am wondering if I should be aware of any significant events that these contracts might remove from the game. Hover the spoiler to see the small one I mention above.
For what its worth, Google led me to a few articles on reasons not to join the Dark Brotherhood that all ended up being speculation, and a post on the gamefaq forums that also did not provide useful information.
One of the first people you kill is Narfi who's sister you can search for if you are not out to get him. This is a very short/minor quest (with not too bad rewards actually) however.
Best Answer
No, none of the Dark Brotherhood's quests intersect in any meaningful way with any other quest chain. Some targets may have minor 'radiant' quests available, but none are significant in any way.
The worst thing that can happen is you can end up with a very large bounty on your head, which could make completing other quests... difficult at best. However, this is both a solvable, and preventable problem.
The only collision other than the one you've noted, is that