Slowbro and Slowking are exact clones apart from SpDef and Def switching. No need to mention them both.
Please add Ferrothorn to the list. Counters Rain and Hail teams and is immune to Sandstorm and takes down sand teams too.
Also mention the usage of Substitute when predicting opponents using Protect to stall out Trick Room. They usually do it on Turn 5 when Trick Room ends, and while that happens, you can sub up and finish them off the next turn.
Edit: Scrafty, Hitmontop, and Hariyama are useful support pokemon with Fake Out, allowing your TR setter to get hit only once. Plus, they have the added bonus of not being as fast, so they can take advantage of Trick Room.