As a user, I regularly add a measure which outputs text to the canvas as the first step of creating a visualisation. When I do this, Power BI Desktop adds a blank visualisation with the measure. It's actually a column chart but since there is only one data field added it's still a large white box with a title.
It would be a better user experience if the default was a Card visualisation. By default I would see the value of the unfiltered measure. I could argue that even if the measure outputs a numeric value, the card is still a more useful default visual.
As a user, when I add a measure to the canvas I want Power BI to produce a useful visualisation immediately. The card visual is built-in and designed for one measure (explicit or implicit). It has everything it needs to be productive with one visual. The visual should be just big enough to display the name and value of the measure without overlapping any existing visualisations on the canvas.
Furthermore, if I add an additional measure to the visual, it should automatically switch to a Multi-row card.
Then if I add a categorical column to the visual it should switch to a bar chart.
If I add a categorical column first, I get a table chart. This is a little slow but a good choice. Sometimes the visual could be smaller to suit the data and reduce the need to manually resize the chart.
If I add a measure to the table view, the visual remains a table chart. This would actually be a good opportunity to switch to a bar chart.