just like with turrets, would love if either by toggle or default that they show their actual range.

I will look into that, but I am not sure if it is even doable.

I think Natural evolution mods has a collector too, and if i remember correctly it shows range... not certain... i don't use it because it's horrible to place down...

Maybe you could fudge it with adding 0 damage, with uncraftable clip weapon to the tower with range = pickup range?

A pickup tower consists of two entities: "chest" (interact-able part) and "radar" (for animation and countdown).
Adding the third entity "turret" for the range will add too much complexity, I am not fond of this.

BTW, I "peeked" into code of other mods. Very often they are using on_tick event to do the additional render. Hope there are more UPS-friendly ways to do that.

Finally have some time to learn about Factorio rendering API, and implemented the display of pickup range in 0.17.4.
Will display range when selecting (hovering mouse cursor) over a pickup tower.
An extra option in "Per player" tab is provided to toggle this off. But it is harmless to keep this option on.

PS: Learned to show this without needing on_tick event at all, thus very UPS-friendly.

The LuaRendering is not too difficult, after first using it will be very easy.

Yes, after using it once, it is now easy for me.

I first peeked into some mods to learn how to do that, where they do that in on_tick event. It gave me the wrong impression that rendering is difficult to be used and UPS-inefficient.

I'm using area displaying by the same mod Active Provider Looting Chest on_tick and just as forever rectangles by the Show Roboport Limits

These would be useful examples before I learned rendering, but I already know that now.