How to indicate sortable elements

Question

I have a list of todo items with 6 properties of which 4 are sortable. The type (icon), the tags, the stars and date are sortable by clicking on them. Name and description are not sortable (no added value). I'm thinking if in the look below it's sufficiently clear to users that they can click, for example on the icon, to sort the elements according to the icon.

The classic way to solve this would be by including a 'sort bar' with carets to indicate ascending - descending sorting.

But I don't like this. It just looks like unnecessary clutter to me, makes it messier and attacks the visual unity while the functionality can be achieved without this. I'm feeling people would like to see this sort bar included but I'd like some suggestions on how to make it clear to users that elements are sortable by clicking on them. Without the sort bar. Any other recommendations are also welcome. Thank you.

Answer 1

I completely agree with the reasoning in Oztaco's answer about expected behaviour, and will add an alternative solution:

You mentioned you want to avoid clutter - you could add a 'sorting' icon such as the one below, which could open a dropdown or expand to show sorting options.

Answer 2

Personally, I think you should leave it up to what users are most used to which is the 'sort bar' you have in your second picture.

Alternatively, you can do what sites like Amazon do and just provide the sorting options in a dropdown menu like so:

These two methods are the most common and users are likely to be used to them. Deviating too much from them may add too much confusion, even if they slightly reduce clutter.

Also, clicking on the icons to sort them may confuse users. It is expected behavior for clicking on an icon to open the item itself, like in file managers, image viewers, etc.