@RBomber @TotallyNotEvil
Hmm.... good points you two. Since we need some numbers, let work this out.
For our Shinobi forces in the grand scheme of things, Let's say that Konoha has about 13,000 active and serving shinobi. that breaks down to about 4,000 genin, 6,000 Chunin, 1,000 special jonin, 2,000 Jonin. only a 10 percent come from Konohagakure, the rest are recruited as an apprentice or in smaller groups outside, trained, and come to join Konoha forces in the late teens the early twenties. the Konoha academy (and its various counterparts) are orient more towards training future Jonin and officers. Your average 'Shuriken throwing nobody' is ranked maybe genin to lower end chuunin. Those who rise above that usually become Special Jonin, no higher. Prodigys, rare as they are outside Konohagakure, do happen though, and they end up in the ranks of Jonin.
Of that 13,000, about 500 (Chuunin Plus) are permanently assigned in Administrative roles in Konoha (running the Library, the Archives, the History, and the Hokage office.) Another 1000 or so are Anbu/Hunter/T&I/Intelligence operatives, many of whom also work out of Konoha but embark on long ops that can take months/ years. there's another 1,500 (roughly equal parts Genin and Chuunin) who are also regularly stationed in Konoha as both standing army and defense force. another 3,000 (Chuunin teams lead by Jonin)on a regular border patrol and watch and another 2,000 (Mostly genin squads led by Chunin officers) as a police/national guard style force (Acting more as detectives and SWAT-style support then day to day policing). Remember, Konoha is fairly large, and centrally placed. Border patrols, in general, are fairly small, but there's a lot of them.
Beyond that, there are also various other bases throughout the land of fire, some of them mere bunkers, others listening posts or supply depots, you know, infrastructure. let's say that's another 1000 or so each of genin and Chunnin, with a handful of Jonin in charge just to keep things nice and even.
The Last 3000 or so unaccounted for ninja are the ones you see. they take missions, deal with customers, guard transports and are hired out. They are scattered across the elemental continent at any one time, with roughly half in the actual and of fire for any moment, either just off a mission or about to go on one. about a third of that (a good 1K) is based out of Konohagakure, under the Hokage's direct command, though only about a 5th are regular in town at any one time. Toru and most of the Jonin/Genin squads are part of that. simply because they are one of the most visible parts of the system.
The reasons for why things like Orochimaru's Sand/Sound attack were so devastating is that is was designed to be multiple large targets, surrounded by squads of skirmishers. Orochimaru used multiple Summons, surprise attacks, and sabotage, and a fair amount of collateral damage to cause as big of a hassle as he did while taking advantage fo the fact that Konoha was spread thinly on the ground during the exams.
Now for affinity part of this. In this story, Fire affinities are either the primary element or the only element in about 40 % of the Konoha forces, a little over 5,000 ninjas.
Earth is dominant for about 15%
and Lighting is around the same at 15%
Water is a bit more common at 20%
Wind is the dominant affinity in only about 5%, or roughly 600, of the ninja. of those 600, only about 40 are jonin, and of those 40, only 10 could be called Wind Ninjutsu
masters. only 3 of those ten are in Konoha. Danzo, Asuma, and (eventually) Naruto. The other seven are posted elsewhere in the land of fire. So When Kakashi Talks about Asuma being the only Wind user in Konoha, it can be taken as Asuma is the only Wind user who can teach you in the village. Danzo is untrustworthy, the rest aren't skilled/strong enough. Wind does pop up as a secondary or gets developed to help support Fire users, but sole wind affinity in Konoha is rare.
Another 5% have stranger natural primary affinities more in line with Either Yang, or Yin, or some bloodline effect. Of these, only about 1% currently focus and develop these (medic, Genjutsu specialists, so on) though they do get developed from secondary affinities as well, boosting the number of those who specialize in such.
Make sense? did i fuck up a number somewhere? let me know!