Well for Tradition I would recommend (and this is just my strategy for tradition) a maximum of of 5-8 cities depending on how many guilds you're willing to but in a single city: 3 in capital, 1 or 2 in each other city depending on how many you've set up.
And as for the vs huge empires thing....I have no idea. VP is biased in favor of wide empires that way sadly.
That's an oft-repeated line (VP = wide), but it isn't really all that accurate. Tourism scales (both ways) based on wideness, and CV is one of the easier VCs to get. The AI loves to attack weak spots, and a wide empire has way more ground to cover. Many late-game bonuses are % or per-pop based, favoring larger cities. The supply cap is about 50/50 flat v. per pop, thus you can't just expand wide and have a bigger army every time. Gold purchase costs for units and buildings, and unhappiness from yields, go up slightly for every city you found. And so on.
I'd say that the definition of 'tall' in vanilla was 4 cities, however the definition of tall in VP is ~6 cities.
G