Since Craglorn is the only location from which to obtain Nirncrux, there is a problem with the current crafting writ system. One has a higher chance to obtain Nirncrux if one obtains a survey map, otherwise you have to be lucky with RNG.
If you have maximum level crafting in Clothier/Blacksmithing/Woodworking, the writs you obtain will direct you to Wrothgar for return, thus having a chance at receiving a Wrothgar survey map. This does not allow you an opportunity to obtain Craglorn maps.
My suggestion would be to have two separate writs options. If you obtain a write while in Orsinium, then it would be a Wrothgar writ: Rubedite/Ruby Ash/Ancestor Silk.
However, if you pull a writ from any other town writ board, it should give you the writ for Craglorn/Belkarth, thus still giving you a chance for Craglorn survey maps. Nirncrux are still highly sought after and are still pulling a premium on the traders at >20k per Potent Nirncrux.
An alternative option would be to have two writ options per board for each craft: one directing you to Wrothgar, and the other directing you to Craglorn for a max crafting character.
Thanks.