Mouths of Parliament of Bugs don't give quests to a Master (or a higher rank) of House Telvanni. Rantela Irenam also doesn't give her quest to a Wizard or higher. It may be realistic (indeed, why bother a member who outranks you?) but it's uncomfortable. There are lots of quests in Morrowind and it's hard to care about their interconnection. A player may concentrate on a specific quests branch and accidentally forget that it affects some other branch, or it may be just inconvinient for him to run circles between NPCs making sure the quests don't block one another. In the vanilla Morrowind there's a kind of rule that all quests are available to anyone except the guild head. A player needs just to hold on the final quest making him a guild head and do all the other guild quests. It is a wise and convinient principle and it would be good to follow it in the add-on.