The existence of an Adventurer's Guild really has an impact on the shape of the city. As others have said, it implies enough opportunities for adventure to support a guild, and for there to be value in joining it.
Assuming that adventurers are common, so will be a broad range of artisans, from armorers to chefs. Selling to adventurers will be a big market. I'd create some sort of Heroes Hill filled with posh homes owned by semi-retired adventurers.
The city would have a guard, but for extreme and magical threats, they hire or conscript local adventurers, among whom the number of spellcasters is disproportionately high.
This is a city used to large influxes of gold and valuables. The cost of living is probably higher than most cities of this size. This means that merchants are more likely to visit, so expect a healthy trade in exotic goods.
Similarly, the roads nearby are probably fairly safe, though I don't know how maintained they are.
In 5E, adventurers have to work to get better armors. They aren't readily available at low levels. This implies fewer master armorers and weaponsmiths. The town probably only has a few, and the city watch and guild probably keep them busy, and wealthy. Apprenticeships are likely expensive to procure.
Speaking of apprenticeships, you'll want people in the city who can train the various skill and tool proficiencies. Artisans probably sell apprenticeships.
I'd expect there to be rather large and established market. Visiting merchants would have tents, but locals would have stores.
Magic items are rare, but spellcasters are probably less so than in previous editions. This town in particular probably has a regular supply of spells available for casting, scrolls, or potions.
Likewise, the number of clerics that pass through is fairly high. I'd expect there to be a shrine quarter. There would be a few local temples for some gods, and shrines for the rest. This is probably near Heroes Hill.
A bit about the nearby keep. Keeps are intended to protect valuables, so a lot of thought would be go into defense against dragons.
Goblinoid tribes are always a potential threat, so building outside the city walls is a terrible idea, and probably strictly prohibited. A few wizards working in tandom, though, can probably move walls relatively easily. I imagine the city built in rings, like a tree, with the walls being moved outward so another ring of city can be built.