Our group's been playing Magic since mid-2013, and Commander 2013 since a while after that. A couple of us are keen on building our own commander decks now. We're aware the Commander format can easily be very powerful, and that different groups vary from decks that finish within a few turns to those that easily last 15-20 turns (like the C13 decks do). We're having some trouble working out how to gear our decks to be at a suitable power level for our table's current meta.
We can tell when a card's just going to outright break things and be un-fun. However, we encounter fairly powerful cards and we're not sure if they're too powerful, or OK because it's just what that deck does, or maybe it should be considered a bomb like Serra Avatar. Is Pontiff of Blight too powerful or just right in our C13-based environment (pay a few {W/B}, cause life loss and get 3-4 life for each mana spent this way because multiplayer) — how do we tell?
How do Commander groups usually work this out? Are there design standards available? Is there a well-defined tier list that can guide our deck construction? What do people go by to ensure they match their game's meta effectively without breaking it? Or is it just done by feel and experimentation and group moderation of "don't use that card, it won't be fun for us, use this one instead maybe"?
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