It holds a certain value in it being the true origin of the long running series, and allows you an insightful view upon the various cameos and pseudo-historical aspects of the Final Fantasy series as a whole.

Additionally, the fact that the numbers and numerous facets of the game are made much smaller, more precise, and generally simply different feeling than much of the newer Final Fantasy titles, it would be worth it simply for that aspect, I think.

And although much the front story is simply an eternal fetch quest drawn out to ridiculous proportions (Get this->This->This->Ad infinitum), the underlying principles behind the story and the character's (mainly enemy's) motivations are something to look into. They are obscure and sometimes disappointing, but if you look closely, you will realize how sacrificial the ending of the story of Final Fantasy I truly is.