I prefer more dynamic challenges than being ordered to make random stuff, don't really care about trade. Stuff like epidemics requiring you to produce elaborate cures, qaurentine your dwarves and keep your fortress from tantrum spiralling before they are all dead. Much more an interesting challenge than a noblemen wanting more random stuff. The same with an insect plague killing all of your crops and you having to deal with a possible famine. Or the king deciding he needs a holiday and you being forced to waste resources on a royal guest.
Fair enough. Personally I'd love to see all those things in there as well, and a return of flooding as well - heavy rains followed by needing to wall off/evacuate your soil-layer caves, or (if you're downstream from the appropriate biomes) the river flooding every Spring when the snow melts and needing to take that into account.
Still, having guildmasters demand more production from their relevant industry and having to build another fancy set of rooms seems sensible enough, and IIRC the one function the guild nobles did perform was to provide somebody for unemployed dwarves to vent at besides the mayor, who may well be busy being yelled at by somebody else.
Personally I think that each noble should get his own personal menu [of course that would require a complete redo of the UI] and should be seen moving around the fortress [or sending a page/runner/messenger] to give orders to dwarves based on what you set in that noble's menu. Make the game a bit less abstract and stuff.
Oh god, yes. I've been saying for a while that the game needs more bureaucracy in larger forts. Guildmasters might be better done as necessary for more than a certain number of workshops of a given type, or possibly to automate certain processes that currently take up effort - instead of using the Manager to order smelting of hematite and lignite and pig iron whenever you want steel, you could use the head of the smelter's guild to just order steel, and see him wander over and meet with the manager - or go to the Smiths' guildmaster and order ten complete suits of steel armour decorated with pictures of terrified elves and have him trundle around to the various other guildmasters to set everything up.
Though that's probably got a lot of crossover with the guildmaster megathread so I'll leave that there.