For fantasy football purposes, crowded backfields are usually a nightmare to deal with. A split backfield isn't as bad, but still a pain. Here are some teams I'm going to try and limit my exposure to. Based on the fact that there are too many RBs getting touches/opportunities.
Houston Texans
San Francisco 49ers
New York Jets
First on the list is the Houston Texans...Well, what a nightmare. I mean not just the backfield, the team in general. But I'm here to talk about the RBs. Which includes David Johnson, Mark Ingram, Phillip Lindsay and Rex Burkhead. Yeah, too many for me to be comfortable with. I'll pass on all of that.
Next is the San Francisco 49ers. When they have a solid RB1 they are scoring plenty of points. The problem with that is they are always changing, and now with all healthy it will be difficult to figure out who will receive most, or any touches. The backfield includes Raheem Mostert, Jeff Wilson, JaMycal Hasty, Wayne Gallman, and recently drafted Trey Surmon. Unless they come out and say/show a clear RB1. I'm going to stay away.
Last is the New York Jets. I like the rookie Michael Carter. But also there is Tevin Coleman, Ty Johnson, Josh Adams and La'Mical Perine. So many new faces as well on the Jets roster who knows if it all can come together. So until I see who the clear RB1 is, which there may not be, I'm going to avoid the Jets backfield.
I also have a few, beware of, backfields. Who have an RB they rely on but don't get the PPR points you'd like with limited usage in the passing games. As well as teams that I just don't see them running a lot or have split backfields.
Arizona Cardinals
New England Patriots
The Cardinals RB1 is Kyler Murray. Lets be honest. Then the RB2 is either Chase Edmonds, who is safer for ppr, or James Connor. Just beware of their usages, they will have their days. But I expect it to be a little difficult finding the days. So be careful.
New England Patriots like to run when the QB is struggling. Plus they are just good at it with a solid O-Line. But, the RB1 Damien Harris, who I love, doesn't get enough receiving work. James White owns that role. Meanwhile for now Sony Michel is still there, as well as the rookie RB Rhomandre Stephenson. JJ Taylor has moves too as we saw against the Eagles. Bill Belichick goes with the hot hand at RB, but if you miss 1 practice after a 3TD game your out, aka Jonas Gray. So yeah beware.
Hope this helps put them in better perspective and light. Now go get that championship!