Over the next 2 weeks I confirmed a few things after experimenting with a couple poster boards from a convenience store.
The bigger the drawing the bigger I can make them. Though if I made them a smaller size from a bigger drawing they were a lot stronger and more durable. Probably from compression of power.
After an accident testing speed where a fox ran into the ocean I found they don't seem affected by water which is good.
After a couple experiments timing my drawing speed It was confirmed that my drawing speed significantly increased. Most under 30 seconds although bigger ones could take longer. I think the speed could be increased if I practiced specific drawings and animals over and over.
Drawing on my skin seemed to get stronger if they stayed on my skin for a bit. Not sure why Though. Another is that if I make a big drawing it can be stored as a smaller drawing before being called out which gives some ideas for more powerful constructs.
I even tried the beast sealing and message sending technique Sai used and they both worked! I have so many ideas for cool drawings coming to life.
It seemed though that I couldn't draw anything other than animals and mythical beasts. Weapons were okay but only if the animal could use them like a monkey with a sword or staff. Could I give it a gun? Unfortunately it turns out no, monkeys can't have guns.