Depends entirely who is going to be writing levels.
This kind of nastiness was prevalent in early id games, where they (deliberately or otherwise) assumed that only knowledgeable experts (i.e. id staff) would be creating levels - and then doom launched a new boom in 3rd party level designers (which were all horrible to use).
If, for instance, it's a core aim of yours to get a thriving community of people writing and distributing their levels, then you should idiot-proof it. If you just want them to have the ability, and expect some to do it, you probably shouldn't bother.
Or, of course, you can go to all the effort of making an almost idiot-proof editor and then not publishing it - like I did with survivor
(but in my defence we haven't released a satisfactory version of survivor yet, and are working on the next release...)