When running a new party, get around the question of plot density by having the first discovery to be a deck of fate, or whatever you call it. If you use a real deck, you should definitely stack it to have the desired outcome, which is to curse the party to attract weird things to happen and involve them. This should not be told to the players at the time, so that they won't just up and try to get themselves 'decursed'. Though quite why they would want to is beyond me.
THE GNOMES OF UDNALOR: Part II
Having left the hush of the upper halls, and crossed the depths of the Braeth (an underground river, which is not all that deep because bear in mind we're talking about gnomes here), you would find yourself in Wattling Street, the main road through Udnalor. It's actually a long, well-worn passageway which opens out eventually into the City Centre. The gnome-buildings branch off Wattling Street as small burrows or caverns with boulder-blocked doorways for privacy. You can find armourers and smiths (though their armour tends to be on the small side for humans to buy) and many other types of trader.
There are many streets, ginnels and cooies which run off Wattling Street, the most famous probably being Smell Street, the domain of the infamous gnomish alchemists, the eponymous smell being very distinctive: the stench of cooking fungus, the aroma of subterranean spices, the pungent reek of rotting carcasses (used in some of the more notorious experiments). An encounter with an alchemist can really be spiced up (excuse the pun) if you have a well-stocked herb cupboard, and actually make up the potions, elixirs and draughts as they are ordered by characters.