I have these ones on my Electra townie. One pin on/off. All alloy and stainless.... and they work really well
www.ebay.com.au/itm/124678566028
I use the Longboard rack from MBB - Moved By Bikes. Great service, took a week to deliver to NZ during lockdown last year. High quality parts and very adaptable to a range of bikes.
I built my own 2 different trailers. One with an old steel tube fence, 3 bicycle wheels from a junkyard and a front fork. This one can carry 3 windsurf boards with sails, booms and masts. Then I built the "light" one with an old garden umbrella's post. This one is divided In several parts so I can transport it on my van.
Haven't really used it while it has been blowing. You definitely know it there but hasn't been a problem for me (at 80kg). Can be awkward getting on with the board and placing it in the cradle... figured out a system that works and no issues now.