Looking for some advice for our steep driveway

I've been thinking the same and now that I've seen the driveway I don't think you'll have any issues. The trailer brakes will stop the trailer, and even without trailer brakes you'll be fine.

I pulled my 6,000 trailer through the mountains for two hours stopping and going with traffic before I realized that I had no trailer brakes. I believe your 3/4 ton truck will handle that trailer with or without trailer brakes especially at those speeds.