each brother plays distinctly different, which is the point

The strength here is that the four brothers actually feel distinct rather than one personality copy-pasted four times. Ace comes across strict and cold exactly as billed, Ryan is noticeably softer as the youngest, and the difference is consistent across turns rather than blurring together. The limitation is that whichever brother you engage with tends to dominate the scene, so getting all four to interact meaningfully in one session is harder than the setup implies.