Please note you can get any of this stuff on Ebay without going through some pretty evil big businesses that abuse their employees and taxpayers.
The American Boat and Yacht Council (ABYC) wiring standards could probably be considered the gold standard for RV wiring as well. Components that can handle marine conditions should be durable and safe in an RV.
Ring terminals are very secure, but the connector crimp is also likely to be a weak spot. Use the correct crimper for the connector, follow the directions, and give it a pull test. I like to crimp, solder, then heat shrink any connection. Double heat shrink when needed.
Note that heat shrink comes in a marine version with a waterproof and higher temperature adhesive inside so the heat shrink doesn't just melt off when connections overheat; it also has a higher 3 or 4:1 shrink ratio. Marine heat shrink should definitely be used for battery
connections to better seal out acid corrosion.
Fuse boxes come in various configurations of common bus, and individually-powered fuses. A negative bus fuse box is probably what you need for a trailer DC wiring system. Having more fuses in the box than you think you need is cheap insurance as long as the positive power feed wire is sized properly for the entire rated load of the fuse box. Wire sizing tables like this one https://www.bluesea.com/resources/529
allow you to just look up the safe wire size.
Spectro Wire and Cable, https://spectrowireandcable.com/products/
a family-owned business, has great pricing on Type SXL primary wire for DC circuits. SXL is much safer than the usual Type GPT found in auto parts stores. Insulation failure on poor quality Chinesium wire can burn your RV down.