Baby boy name you love but fear is overused? Here are some possible substitutes.

Names to Substitute for Nicholas

Excellent candidate for use as an undiscovered surname name. Niven is the Anglicized spelling of the Irish name Naomhan, a diminutive of the word naomh which means saint. This handsome but unusual name was given to only six boys in the US last year. Your parents may be familiar with actor David Niven.

Niven

Homer is a name that has traveled from the ancient Greek scribe of the great classical epics to Bart Simpson's doltish dad, and has also become the surprise hot celebrity pick of such parents as Richard Gere (his father's name), Bill Murray, and Anne Heche. Simpsons creator Matt Groening has both a father and a son named Homer.
 Because of the epic scope of The Odyssey and The Iliad, the term "homeric" implies work on an enormous scale, while "homeric laughter" references the unrestrained laughter of the Greek gods.
 With its quirky resume, Homer could make an interesting choice.

Homer

This is the second-to-the-original spelling of a name that's part Jersey Shore, part upper-crust British.  Dominick gets you more directly to nickname Nick.

Dominick

Very popular on its native turf, foreign-sounding here. 

Alexios

Kenyon is a very engaging British surname name, the middle y giving it a kind of southwestern canyonesque undertone.
 Though Kenyon appears in English records as far back as the fourteenth century and arrived in America in the seventeenth, it sounds cooler these days than the more traditional Kenneth. Kenyon has literary ties to the prestigious journal The Kenyon Review, originating from Ohio's Kenyon College, and sports enthusiasts will recognize it as the name of basketball star Kenyon Martin (nicknamed K-Mart), the first pick of the 2000 NBA draft, who plays for the LA Clippers.

Kenyon

Attractive, approachable, and more striking Nick alternative. 

Nikos

The name of one of the greatest Western philosophers is often used as a first name in its land of origin, Greece, and would make a really interesting, thought-provoking choice here. It is remembered here as the nickname of the memorable character played by Sal Mineo in the classic film "Rebel Without a Cause."
 And speaking of Greek philosophers, Germaine Clement of Flight of the Conchords named his little boy Sophocles.

Plato

Christos

If you're looking for a Nicholas substitute or namesake, Nicholson would make a more distinctive path to the likable nickname Nick, fitting in with other newer patronymics like Anderson and Harrison. Unusual but not outlandish, it is associated with writer Nicholson Baker, library advocate and author of Vox. And as a surname, of course, with Jack.

Nicholson

Often used in England, but here likely to be confused with the feminine Nicole. Nicol Williamson was a Scottish-born actor once described by playwright John Osborne as "the greatest actor since Marlon Brando".