Honestly, I would put the Jedi Consular at around 17500 because it says in the prolouge/intro that the consular's count was one of the highest recorded in the order at that time. That said, it still must be lower than yoda (18,000) because it is known Yoda held (or at least was close to holding) the record until Anakin came along.
With that in mind, I would put the sorcerer (post-chapter 3 (thanaton's defeat)) at around 19,000 or 19,500 effective midichlorians count. This is due to the aid of the sith spirits he absorbed which technically don't have midichlorians due to being non-living and thus having no cells to speak of, but at the same time are heavily implied to have increased the sorcerer's ability to communicate with and influence the force (which is midichlorian's exact function).
At the same time, there is a whole story ark where the sorcerer has his body rebuilt by a Rakata god-machine (the Mother(?)) so that his body could handle the power those sith spirits were channeling into him (it was literally enough unhandled power to tear his body apart in a matter of months (weeks?) if the story is to be believed). We can assume that this rebuilding took the form of bumping his count up a fair amount, among other things.
Though it was probably closer to 14,000 or 15,000 as a raw number at the time of his intro. High but not at the absurd levels of most of the others. It's just the aid of the sith spirits and the rebuilding of his body to handle them that make it hard to measure the final number. The sorcerer is the only class where it can be assumed his count jumped significantly through his storyline. It can be said that the sorcerer is least limited by his midichlorians where not just his power, but even his potential is concerned.
If the rebuild didn't affect midichlorian count, then I would say that the sorcerer is entirely unbounded by any limitations to his potential that they would imply due to having found an entirely different medium (the sith spirits) through which he could influence the force.
I would put the knight a fair bit lower than the consular, so lets say 16,500. He did defeat the emperor after all, but at the same time not much fuss was made about the knight's potential in the force. So honestly, I feel it could be much lower than the rest, but it is stated the knight is a prodigy otherwise (in the blade for example) so his mastery over the force and skill with the sabre is what gave him his actual power and ability to defeat the emperor.
Think Obi-wan. Obi-wan had a rather low count as far as Jedi masters go, but he could still compete with most of the sith of the era (obvious exception for Sidious). This was due not to his power in the force, but his mastery over it and his skill with a sabre. Hell, the scene where he pummeled Vader in his show proves mastery is worth a lot.
Finally, the sith warrior. This is an odd one. A lot, and I mean a LOT of fuss was made over how people could just feel his power. And the warrior does have a lot of cutscenes where he just casually force-slams two guards into each other.
I'll put the warrior at 17000. Less than the consular (who is said to hold or be near a record), but more than the sorcerer (in raw/starting number at least) and the knight.
It has to be that high, since its clear the power he shows in the cutscenes wasn't gotten through effort. The warrior's failure to recite the sith code to Baras is proof he did not put much effort into training.
That is my rating for the midichlorian counts of the force-wielding classes.
Sorcerer is debatable since we don't know what possession of the sith spirits and the reconstruction of his body actually did to him. It could be as high as 22k, or it could be unchanged, with the nature of the power being similar to Darth Nilius (who only had about 15k himself, but due to the nature of his power could still consume the life force of entire worlds and display power comparable or even superior to Vitiate (who has 25k)).
A few benchmarks to keep in mind:
Yoda: 18,000
Sidious: 20,000-21,000
Vitiate: 25,000
Anakin: 23,000-40,000 (depending on source)
Revan: 17,900
Xar Kun: 19,000-ish
Darth Nilus: 14,900
Obi-wan/Plo-koon/Kit-phisto: 13,000
