@satobox: the -INF +INF was simply an example, i know it is no practically possible setting for this kind of thing, but from your own suggestion i see you get what i mean 
i also agree with you on TheBellow’s arrows being unnecessary. for incremental switching of values can be done through a click+drag, as is the case with, for example, the DSP chain ‘master’ device’s delay setting.
(in fact, i think it’s true for all blue-colored values and not for the white ones. this is kinda strange, but will make a new thread for that - update: here it is!)