Shigeki sits next to 3 phonetic neighbors — Shigeto, Shigeo, and Shigeru are the closest matches by sound. Most share Shigeki's Japanese cluster, so the rhythm and vowel shape carry across the list.
You searched for names like
"prosperous tree or thriving tree"
"cotton plant, soft white fiber"
"listen, hear (Latin)"
"gentle, kind"
"cause of rejoicing"
"Self-reliant, self-sufficient"
"from Attica (Athens region)"
"yarrow plant"
"Pattern; model; example"
"powerful, heroic"
"Gift of God; one who is like God"
"hope"
"breast, rounded hill"
"of the mountain"
"God is gracious"
"full of life, lively, alive"
Similar sound: These names share phonetic patterns with Shigeki — similar vowel sounds, consonant clusters, or rhythm.
Shared roots: Several names on this list have Japanese origins, giving them the same cultural heritage as Shigeki.
Rhythm: Shigeki is a 3-syllable name. Names with the same syllable count tend to feel interchangeable when you're narrowing your list.