Learn German: Die neue Choreografie verlangt viel Eleganz. - The new choreography demands a lot of elegance.

When viel (much or a lot of) is used without an article before a singular, uncountable noun like Eleganz, it remains undeclined. You only decline it when it describes plural countable nouns (like viele Tänzer) or when it follows a definite article (like das viele Geld).

Is Choreografie spelled with an f or a ph in German?

Both are correct! Following German spelling reforms, many words of Greek origin can now be spelled with f instead of ph. Choreografie is the modern preferred spelling, but Choreographie is still widely used and perfectly acceptable.

What is the gender of Eleganz and is there a pattern to help remember it?

It is feminine (die Eleganz). A highly reliable rule of thumb is that almost all German nouns ending in the suffixes -anz and -enz (such as die Distanz or die Tendenz) are feminine.

How does the verb verlangen work if I want to state who is receiving the demand?

In this sentence, verlangen (to demand or require) simply takes a direct accusative object (viel Eleganz). If you want to specify who the demand is directed at, you must use the preposition von followed by the dative case. For example: Die Choreografie verlangt viel von den Tänzern (The choreography demands a lot from the dancers).