Proper rims with modern design have given us rims with lateral stiffness previously unavailable with old fashion high bead rims such as Mavic/Rynolite/Alex etc. We can thank the tubeless mountain bike rims for making them mainstream. Looking at the design of wheels that are require to withstand the most abuse, downhill, we can learn new concepts that replace the canard about double butted spokes and flexible rims offer the best service life.

Using a rim such as a 520gm Stans notubes Flow EX allows lighter yet stronger rims compared to classic touring rims such as Mavic 319/719 (600gm/540gm) they also allow us to make the move to tubeless as it becomes mainstream of road just as it has for mountain bikes and gravel grinding.

My Stans FlowEx, 32 spoke, 2.0mm straight gauge spokes are stiffer than my previous 36H/319 rims and offer wheels that will never break spokes, esp for road touring.

I've also had great experience with the new SunRingle TR Helix 25 and 27, lateral stiffness and tubeless ready for less than $60/each.

If you need a brake track the DT tubeless rims are great although a little more expensive for the higher weight versions such as the RR511.