The following list is what I'd consider a minimum for a solid team to match up well into opposing balance/bulky offense, and not instantly lose to common matchup fish, in this case rain and malamar. If your opponent has no history of using at least one of these bullets, feel free to ignore said bullet, at your own risk of course. The pokemon listed after each bullet are examples, are are not intended to be every option you can use to check said mons.
Checklist for Balance / Bulky Offense (in no particular order):
1) Archeops / Tauros Check(s):
2) At least 2 mons that check Kabutops and Ludicolo with rain up respectively
3) 2 Fighting Type Answers or Weezing
4) Mesprit Check (avoid a 2hko from specs psychic)
5) Pokemon that can switch into Vileplume's Sludge Bomb, get poisoned, and do so again, or 2 pokemon that separately can switch into vileplume once
6) Volt Immunity: Ground Type or Lanturn (Audino can do this in a pinch)
7) Malamar counter

(Worry Seed)
8) Hazard Removal (if you are running 2 SR weak mons consider removal + scarf removal)
9) Steelix abuser (Xatu is great for this, but generally you need a mon that switches in and punishes their team)
10) 2 Fire Checks (don't lose to Mortar on preview)
11) Speed: Ideally you want a scarfer faster than at the very least Tauros, but having 1 mon above 100 base speed and 1 scarfer is ideal to ensure you can grab momentum more easily.
