Hey @Gwydion ! Welcome 
Many have answered your questions, but I’ll give my input as well, just in case:
What do you do to relieve the boredom? Wahoo has entertaining Sufferfest, ProRace and On Location videos which make an hour’s workout fly by. I was struck by how long the hour felt on TR, so what do people typically use? Zwift, youtube, netflix, audiobooks?
As @Elgro mentioned, you can send your TR Workout to Zwift to complete them in their virtual world with the TR-Zwift Integration.
Tumbe is a pretty simple workout, are there more involved ones which demand more dynamic changes e.g. dynamic cadence target, seated/standing changes?
As @Elgro also mentioned, the workouts come with instructions, but you can also choose a Workout Alternates to see if another one interests you more! This is a good way to pick a workout that keep the energy system meant for the day.
Is there a way to integrate Apple Health so that TR gets my daily weight, for example?
Not as of right now, however, you can connect your Apple Watch so that TR can analyze TR Outside Workouts that have been recorded on your Apple Watch.
How open are TrainerRoad to suggestions? There are few small things that Wahoo’s UI does better and wondering if there is a place for feature requests?
Very open! We have a features thread here: TrainerRoad - Feature Requests of what athletes expect / want in the future - #1139 by ToddAMelton