brenlo's list "Boy Names with Long I Sounds" of 4 great name ideas: Wilder - Wild!

Boy Names with Long I Sounds

Boy names in the top 500 range which contain an I which has a long-I sound when pronounced.

Rugged, outdoorsy, and full of energy, Wilder entered the US Top 1000 back in 2015. Part bad boy, part Western, part preppy, and part nature-loving, Wilder is given to nearly 800 babies each year.
 
Once an off-beat, rarely used choice, Wilder began to climb the charts in 2007, after American actress Goldie Hawn became a grandmother to a Wilder. Similar in sound to Wiley and Wyatt and with the -er ending of Carter or Cooper, Wilder sounds bold but familiar, and fits in with the likes of Ledger, Forrest, Fox, and Maverick. Until recently, Wilder was much more familiar as a surname, borne by such notables as authors Laura Ingalls and Thornton, composer Alec, director Billy, and actor Gene. Douglas Wilder was the first African American to be elected Governor of Virginia. Wilder was one of the 10 fastest-rising boys' names back in 2016, though its climb up the charts has slowed in recent years.

Wilder

Leonidas is an ancient name that has started rising again along with centuries-old names such as Augustus and Cato. The original Leonidas was the most famous of Sparta's warriors, sacrificing his life at the Battle of Thermopylae; there is also a saint Leonidas. More stately than Leon, more melodious than Leonard, Leonidas is a leonine name that commands respect. In Greek, the name is pronounced leh-oh-NEE-das, but Americans tend to say lee-oh-NYE-dus.

Leonidas

Kaiser, as in roll and Wilhelm, appeared for the first time on the US Top 1000 in 2017.  It fits the two-syllable -er ending style that's all the rage, and it lends itself to the short form Kai.  But we hope this Germanic version of what is essentially a title rather than a name doesn't keep rising on the charts.