I totally agree. I remember a thread in general discussion a while back when it was first stated that flares would have a set duration, but improve chance-to-hit or something. Right now, they have the duration, but it doesn't have any benefits, and even if it did, something that could be placed in bases would still be wanted.
This item could have the same effect as pre-wipe flares, but just be an item and not be a weapon. Its default sprite should also be smaller [or non-existent, use G to pick up?].
When devs made the "pre-wipe madness" change that made all tents and bases visible, I saw many amazing designs that used a combination of broc/xander, Gamma Gulp/Rum, and the red and green flares. I would very much enjoy being able to do this again.
Right now, the only thing we have is Gamma Gulp. Other colors of flares, and more ranges in the light they create, would also be appreciated. The item could be called just "Light (color)"
As a side note, other things, like burning barrels, could become items too. They could rarely spawn in some merchants' inventories from time to time. I know this is possible and does not interfere with the whole "non-dynamic maps" thing.