Cas

• Same eraLangstonLike Cas, it was given most in the 2010s.#999 · falling
• Same rhythmLevSame beat as Cas: one syllable, ending on a consonant, but it starts differently.#999 · steady
• LongerKabirTwo syllables to Cas's one: a long name beside a short one keeps them distinct.#999 · steady
• RiskyCashOne letter away from Cas. You'll call the wrong one for years.#287 · steady

Suggestions come from names in this year's top 1,000. Rhythm and rhyme are judged from each name's pronunciation (Wiktionary's, or espeak's reading of the spelling), so a few calls may be off.