It would be handy if we don't have to deselect a previous roulette to select a different one, i.e. if we try to select a roulette and already have another one selected, it should automatically deselect the previously selected roulette (without having to click on "Clear Selection" or manually deselecting the previous one). The DF interface already does this if you select a roulette while having other (non-roulette) duties selected, so why not do it consistently?