Explain the problem as you see it
Since Tana falls in line with outlines like Dynalist and Worflowy. Whether this is intentional or accidental I don't know). But a distinctive feature that promotes these applications is the execution of a line or task by a keyboard shortcut such as CTRL+ Enter in Windows. In Tana this function is implemented, but in such a way that the string is turned by the first press into a task and by the second press into an executed task, but remains in the list. This creates multiple keystrokes. Perhaps you wanted to exclude this function. But at the moment we cannot quickly create and execute tasks, as well as cannot quickly hide completed tasks. That speeds up the work and gives a huge advantage to the application. You can't quickly turn off completed tasks. You can't just turn off rows as tasks without dividing them into tasks and text. You can't compare the speed of work with the thread like in the above-mentioned applications.
Why is this a problem for you?
This slows things down, and keeps things from working quickly. In my opinion it is a great feature that you have created in a peculiar way, but it is that unique offer that outliner app gives.
Suggest a solution
Enable Worflowy's analog function. Hide completed lines. Keep the functionality you have, just rethink the key assignments. To create or line task and so on.