Well, a god of sleep and dreams with a youth connection could be worshipped by a whole mess of people worried about youth and aging.
Other important aspect of worship, however, would be protection while sleeping and dreaming and asking for particular types of same. Everyone would pray for protection, and some who suffer from madness, paranoia, thieves, and so forth would pray for succor. Many would pray for specific types of sleep and dreams. A specifically sexual aspect would undoubtably develop as those who wished to sleep next to others would pray for aid. People seeking to dream of lost or unknown things would also seek aid, so anyone who needs inspiration.
Related professionals would be devout worshippers of the god. Nightwatchmen who must protect others while they sleep and also need protection from sleep. People who deal with the insane or disturbed. Travellers. Innkeepers. Revellers and organizers of revells. People who need inspiration. Detectives. Teachers. Many people in medical professions. Hunters and shepherds.
People who want others to be vulnerable while sleeping would be a distinct cult. So their would likely be a thieves and assassins form of the church.
Prison guards would have a very particular relationship with the deity. The sandman comics do a lot of riffs on the importance of dreams to those who make prisons and I find that both striking and true. And prison guards really need to be protected from sleep.
Whatever weapon is commonly associated with nightwatchmen would be my pick for favored weapon. Though garotes, nets, lassoes, and bolas might also work as they have to do with either capture or unconsciosness. Some form of fighting torch might also work. The light of dreams and those what protect you while you sleep and party and what not.
Ancestors and community is actually going to be pretty related to Morpheus. People will want to dream of thier loved ones and be protected from night terrors.
A deity of Ancestors and community is always very powerful and popular. Vesta in ancient Rome, for instance, had no power in the theology but her priesthood and cult had a lot of power in the city. Very often associated with the hearth.
Worshippers would be anyone who ran a family or community and anyone who would be a supplicant to the above. The god or goddess would also enjoy universal worship whenever a large scale community event was being celebrated or endured.
The other aspect of worship would be the elderly, the young, and funerary rites. The elderly would seek aid in being proper ancestors to the youthful and future generations. The young would seek guidance in dealing with the ancestors or guidance from honored ancestors. Anyone who had just lost an ancestor would be very interested in worshipping the deity for the wellfare of their departed and their own ability to remember and honor them properly.
Related professions would be anyone involved in burial, lawmakers, community servants, historians, sages, politicians, religious leaders, public works architects, people who use public works, and crusaders of various types.
Favored weapon would be whatever is associated with general authority and guidance. Traditionally this would be a staff or rod/mace. A conservative but strong weapon with plenty of peaceful purposes. Particularly militarisit cultures might have a traditional weapon that is associated with their bond with the community. Like Claymores and Skean Dhu for Scotsmen and the daisho for samurai.
Sound like great deities. Good luck with the campaign. I always like to hear about it.