Comparative degrees show, obviously, degrees of comparison. The more common expressions involve "more" and "most." If you think about it, this mechanism is actually used to *describe* states of being...well, nouns and pronouns, and verbs; therefore these degrees exist only within adjectives and adverbs.
Unfortunately, the word "up" is not primarily an adjective or an adverb, although it can be used as such. It is a preposition, used to show how its object is related to the general concept of the sentence they happen to be in. Used as an adverb, it's usually found at the end of a sentence, as in: "English moves you up." This is, let's face it, rather irregular usage, although by no means grammatically wrong and unacceptable.
So is there a comparative form for the word "up"? "More up." But it's clumsy, okay, so I suggest that you rephrase your sentence in order to move around this problem.
Cheers.
more full, more up
Teapot is a noun and, as such, does not have a comparative degree.
The comparative degree is bigger.
The comparative degree is wider.
"Less" is the comparative degree of little.
The comparative degree of "holy" is "holier."
Thriftier is the comparative degree of thrifty.
The comparative degree of "light" is "lighter."
The comparative degree for "lush" is "lusher."
"Speed" is a noun and a verb and, as such, does not have a comparative degree. The comparative of the adjective speedy is speedier.
better for its comparative and best for its superlative
"Less" is the comparative degree of little. The superlative degree is least.