You would be safe with a Nitecore i2 , i4 , D2 , or D4 and I would not suggest anything LESS than these.
They are inexpensive on Amazon [if you shop them]
Never have I had the batteries or the chargers even get warm.
In my cluttered desk situation, I keep the power cords plugged in to a power strip, and laced into the corner of my desk. When I need one of the chargers, I load the batteries and plug the power cord into the charger.
My reason for more than one charger is because on most chargers, the more batteries charging at once, the lower rate charge for them.
I don't have a device that requires more than 3 batteries to run it, and I always marry batteries, so I don't need to have a charger with more than 3 bays, so the 4 bay is fine. I also have enough spare batteries that are waiting in the wings to use. If I need to charge any others during the several hours it takes to charge what is charging, I have an additional charger to begin on them.
Of course there are more sophisticated chargers, for more $$$, but personally I don't see the need for 18650's and similar. The couple of chargers that are top of the line really are no safer, some may charge a bit faster, but sometimes faster also means more heat.
I think a Nitecore D2 or D4 is safely efficient for what our use is, and my recommendation.