Questions on an enclosed trailer

I have a 12 foot open and a 12 foot V nose enclosed trailer, both have double 12 foot E-Track installed. Best add on I made to the trailers. I used stainless bolts and nuts with surface washers on the bottom so I had maximum strength for the attachments so I didn't have any localized loading problem that might pull out a wood/metal screw. I put them every foot or so making sure I hit all the frame supports underneath. I am using it to tie down fairly heavy loads at times is why I over did it. I was going to ad it to the walls also, a friend did and it works well but I decided I wouldn't use it enough to bother and instead added some tie down rings up high on the wall every 3 feet or so and a few lower where I needed them to tie specific things.