Between my wife and I we are running 7 decks but 2 are precons that I've put together an upgrade list for but haven't pulled the trigger yet. Our top decks are currently
K'rrik, Son of Yawgmoth,
Arcades, the Strategist, and
Pir, Imaginative Rascal //
Toothy, Imaginary Friend.
My wife has a really fun Dino deck that she plays most often but it is a little on the slower side. However, if it is not kept in check it can get out of hand quickly.
My Pir and Toothy deck is the one I play most often and is the first EDH deck I built. I have gotten pretty good at piloting it. I don't think any of our decks are above a 6 or 7 on the power scale but for our play group that is right in the sweet spot. We just don't have the budget to fully optimize our decks and tend to have more fun building and playing a wide verity of decks rather than focus on going all out with 1 or 2 of them.
Since the power scale is a little subjective I have listed what our play group uses.
Power scale in my play group is as follows:
1-2= Jank, no real wincon, and gets shut down quick.
3-5= Precons and budget (we some of the 2017 & 2018 decks) Focused and effective but with room to improve.
6-7= Focused, good synergy, and modest budget ($350 max). These are what we bring to the LGS and can hang with some pretty solid decks.
8-9= Optimized, high synergy, big budget. Can normally go off on turn 5 or 6.
10= cEDH