5-6 Pendulums is usually considered the most consistent. I have no problems with using 4-5 Pendulums as the latter gives you a 5.5% chance of not drawing one in your first hand, but other people complain so meh.
As for creatures, it ultimately depends on the PSNbow you're planning on running. Generally most use Entropy Pends which as a consequence means less
creatures/spells/permanents should be used to stop the risk of interfering with quanta from Supernova. At most the creatures from Entropy should be 2-3 and should never exceed 4 or 6 quanta.
Instead, I would recommend focusing on the creatures matching the Mark. The two decks I have in mind as I type this both use Entropy Pends and 4 creatures matching the mark. However, the cost of both creatures in this case is 5 quanta; you can offer a bit of flexibility here in that case. Your individual QI for the creatures you choose should not exceed your quanta production. For instance: Fire Mark, 6 Entropy Pends means you have a QI production of 4
. 4 Lava Destroyers would mean your QI consumption would be just about 4
as well, making it perfectly balanced. I would imagine 5 Pendulums would provide almost the same results.
http://elementscommunity.org/forum/index.php/topic,20665.0.html
read this...
I personally didn't find this very helpful in regards to the original question.