I really do not care for any hinge stops, but sometimes they are a necessary evil. I've found that if they just have to be used, they perform better with one on the top hinge and one on the bottom. This helps distribute the weight and does less damage to the door. I would want rubber bumpers on anything that makes contact.
If I had floor drains in a basement or garage I would want them draining out as yours, but I am kinda surprised that you are getting away with the floor drains not going into the septic. My understanding of TN regs is that any drain under the roof of the dwelling has to run to the septic.
I knew of one guy who wanted drains in his garage so he could wash his cars inside during the winter. Codes said no can do unless ran to septic. He argued, "you mean I can wash my car just a few feet away in the drive and the wash run all over the ground but I can't do it in the garage and let it run out the drain onto the ground". Codes held their ground. He skirted the codes by installing the drains, covering with newspaper, pouring the concrete over, and chipping out the thin layer of concrete later.