Just like the TG quests where you have the guards clearly showing their 'magelight'... it's completely fair to expect that using RM would do the exact same thing... allowing your enemies to know you are trying to detect them and making it easier to avoid. Those who are complaining about it clearly want your cake and eat it too... you cannot have it both ways... trying to detect but not be detected doing it.
I have never actually found anyone using Evil Hunter/Magelight, so I just always use detection pots.
Not only should they not be able to tell who is using these skills but the range should be doubled or tripled. Cloak and sneak are too powerful currently, especially since the NB spammable alsodeals high damage, debuffs, and stuns you (while passively granting you huge amounts of resistances for some ridiculous reason) when applied from stealth.