In my experience, Dustbowl is especially reliant upon a well-balanced team. Every class in TF2 has its counter. Its largely a matter of identifying the other team's weaknesses and exploiting them.
RED has 5 sentries out of the gate? Get a couple spies and a ubers. They will have too many engies, which means too little support to stop a solid push with ubers/saps. It may take a few tries, but once you break through the sentries you can roll them. Once you roll the first point, it can be difficult for RED to set up again on second point before your team comes barreling through to roll second.
Almost every time I die, I check the class selection to make sure we aren't unbalanced as a team. I try to switch to the classes that we need, and avoid stacking anymore than 2 of any class.
It is good to have sentries, but if you don't have solid classes to help protect the engie, the other team can flank and conquer pretty easily. Medic is a necessity on both teams -- I will almost always fill that if there isn't one already. Other than that, I just try to counter their strongest players with my class selection. IslaDePaz is mopping us up with pyro? Go Heavy. Quicklightning is holding us back with mini-sentries? Go Demo/Soldier. Mochi is decapitating the whole team with his headshots? Go Spy.
One of my favorite things about TF2 is how well balanced everything is. There is ALWAYS a counter. It is just a matter of being proficient in all the classes so you can fill the necessary role. I still need a lot of practice as Sniper and Scout, and I am slowly getting better at Spy. I am at least decent with everything else. This allows me to fill my team's weaknesses and counteract the other team.
Anyway, I'm not sure y'all wanted a serious answer, but there it is. I love Dustbowl, and I love the strategic elements of TF2.
