Our club has an rwgps subscription, so anyone that uses the app for our routes gets all the premium features for that route, including downloading if for offline use. For managing our routes I'm not sure there is anything better out there, and it's not the worst way to navigate a brevet, some riders I know use it for the audio cues and it seems to work well for them.
I don't really use it to navigate though, usually just look at the elevation profile. Any routes I design have some extra information put into the POIs that rwgps uses, they're added to the cuesheet just as "optional services" or whatever, but there's more room in the app to put in restaurant names and whatnot.
I've had good luck using maps.me for offline navigation, though I end up modifying their suggested route into something that suits my riding style... maps.me (and google/rwgps also) seem to love using busier roads around here, and snowmobile trails, private farm lanes, utility RoWs, etc. so one needs to be mindful of the generated routes.