Yes, factitious cares is used as an object of life. Note the definite article the immediately preceding it. This indicates that Thoreau is talking about two things in the same context: "The factitious cares of life" and "the superfluously coarse labors of life". Had he wanted to indicate that the factitious cares are merely general things and not specifically related to life, he would have written:
". . .so occupied with factitious cares and the superfluously coarse labors. . .
Thoreau is making a statement about people who lead boring and artificial lives through their own ignorant mistakes. Let's take a look at the meanings of factitious and superfluous:
Factitious: Not genuine or natural but created deliberately and made to appear to be true. (OALD)
Superfluous: Excessive, unnecessary, needless. (Dictionary.com)
Factitious cares in the given context therefore means that Thoreau considers most people to be engaged in pursuits that are not natural to them. The people to whom he refers are not working for real, genuine, useful things, but for created ends that serve no real purpose. Worse still, they're unaware that what they're doing is ultimately useless.
Superfluously coarse labors indicates Thoreau's disdain for what he considers unrefined goals and pastimes. He thinks of what the average person does as being excessively crude or unpolished.
To restate it in modern non-poetic English, Thoreau is basically saying:
Most people waste their freedom of expression and thought because they don't know any better. They put too much time into artificial and unnecessary pursuits, and because of this they don't get to enjoy the genuine and good things life has to offer.
Or, more casually stated:
Stop worrying so much! Enjoy the good things in life and don't get bogged down in the daily grind.
Factitious is not in general use in today's standard English. Most people will have to look it up, and it is easily confused with facetious. (I certainly had to look it up, and I did confuse the two words.) You're probably better off using artificial or constructed if you want to convey a similar meaning.
This usage is correct. Here, more than is used with a verb. Look at the sentence
The number of children doubled.
The verb here is "doubled," meaning "increased to a new amount that is twice the original amount".
We can use "more than doubled" to mean "increased to a new amount that is more than twice the original amount":
The number of children more than doubled.
This is a normal use of more than for "multiplier" verbs like double or triple. To confirm this, you can do a Google search for "more than doubled", which shows the phrase used by Time magazine and official agencies like the CDC.
Using more than with adjectives is also normal (but that is not what is happening in your example):
She is more than angry; she is furious.
They are more than just strong; they are also very fast and smart.
Best Answer
The noun "globe"(our planet) can take prepositions across, all over and around/round. I think that if it means a sphere on which a map is represented, there may be something on it.
I'd use "the highest/biggest/greatest number" instead of "most number" though.
As for the adverb arguably, to me, it's position in variant B seems to be preferable to that in the original sentence.
Although if you paraphrase the sentence using a literal meaning of "arguably", it may read without any change of the idea: