Word or short phrase similar to "self-centered" but not judgemental, condescending, or insulting
"Introspective" means "turned inwards," and can have positive connotation. It could suggest focusing on one's self with a view toward improvement, or at least a dispassionate view, not just self-adulation.
You are seeking an ameliorated version of tends to be self-centred.
Somewhat insular; may lack a broader view; can be solipsistic; shows some signs of adopting personally orientated solutions; would benefit from being less self-contained.
Fronting almost anything with "Occasionally..."; "Has shown a few instances of..." "Should look to improving ...", etc., may help.