Adding an endurance block at the end of a workout is widely considered to be a ‘save’ way to add some TSS to your training. But its not easy to do.
Two easy features could make this possible:
Extend cooldown lets you add time but clicking on one of the options closes the popup. So adding 30 minutes means clicking on extend cooldown 3 times and selecting 10 minutes 3 times. If popup stays open and a close buton is added you could click on 10 minutes 3 times and then click close.
Cooldown is usually around 30% ftp or so, so thats clicking on +1% intensity 133 times to get it to 70% of ftp to have an endurance block. Why not have +1%, +10%, +100% just like on the Wahoo Elemnt?
Now I fire up my Wahoo Elemnt one minute before TR workout ends, put it on 210W (70%) and cycle on for 20 to 30 minutes. But I get 2 strava rides.
I just have a second endurance workout pre-selected. Once my first workout ends, I just stop long enough to fire up the second workout. Takes less time than a stop for a traffic light, so no impact on the overall training.
If you data is getting uploaded to Strava via your Wahoo, it will still come through as a single file.
Like many suggestions, there are already existing Feature Requests that cover your ideas. We prefer a single forum topic per idea, so please add your comments to the existing discussions as appropriate.
Per your #1, with the addition of Adaptive Training, that method of extending the workout is not really the best method if you aim to add more than something like 5-15 minutes. If you want to add 30 minutes or more, you are better off to finish the first workout, and load a separate session that suits your duration (not to mention intensity, which side-step #2 above).
I am tempted to refine this topic into a feature request about just your #1 idea, following the forum preference at the very least.