Very annoying. This is just my 5 stage in on normal and I’m facing cabooms that kill my team on just his first ride through - every time he gets that bike going someone dies and each stage is a battle to contain him while goofy wreaks havoc on the side.
Is there any way to avoid this problem? It’s pretty much every stage now and it’s just Normal - I have to keep my best toons fighting just to have a chance, which slows down my Collection progress…
Yeah. Get Baymax (if not on Server 14) or Calhoun (Vi)
Or Violet(Me) 
On the wider issue, CW pulls its teams from Arena, which is why you’re seeing so many Goofy & Duke.
Also, the difficulty makes no difference - you will face the same lineups regardless of which setting you choose, only the modifiers to your own team are what changes.
I’d do whatever you need to do to get through the CW, and take any collection progress as a bonus 
you should still be able to use the first few stages, at least, to work on other heroes.
Thanks for the tips…didn’t know about the comps being the same across all the difficulties. I’m server 19 so no Baymax, and my Calhoun isn’t too farmable just yet. Violet’s one of my counters but the damage is so extreme he one-shots some of toons thru Violet’s white + half of their health…that’s what made me so infuriated.
True about arena too…3-star Cabooms sure are ruining my day all over arena 
just have to suck it up for now like you say and take whatever victories I can manage.
Thanks!
I, too, am on S19. Hopefully the new heroes as well as Ducky and Bunny should shake the Goofy/Caboom meta up a bit, but it won’t be an instantaneous change. A handy tip for CW I remember seeing somewhere is to unequip your friendship disks on your main team before you restart CW, so that your team power is lowered and the teams are slightly easier.
This reminds me of the game I came in here out of: Star Wars Galaxy of Heroes. They had a nightmare City watch too that had everyone trying to guess how to game it…
That is true, if you remove the discs of your top 5 toons it will be slightly easier because the difficulty level is based off of that. Unfortunately if you are pretty even across the board you’ll sometimes have to remove a lot more than 5 because they keep changing order as you remove them. 
But it will help you get through easier! Good luck!
Update: this problem is largely solved now, with some careful tuning of my team.
I have a new problem now: Goofy, Duke and D&B in every match. Sobs.
Seriously, both the City Watch matchmaking and D&B’s damage needs to be seriously tuned… The 3 of them appear in every match now, and require nothing less than the best toons each time to take them down, which pretty much are the same mirror toons, which is really lame. I’m having difficulty getting enough energy to do so too: strangely enough even when I get an energy boost over them leftover from earlier matches they always get to their Whites earlier.
There’s just something to be said about fighting each match trying to avoid that one instant where - Shields or not - half the team evaporates under a laser glare. This is exasperating…