No beveling, I need align it to outer edges. So, this mean automatic subdivision(needed iterations count depends from poly size, and probably nearest faces angle in between). For example make 5 pseudo quads from large tris group (2 in one layer) and move new edges around on calculated distance to reach more round surface of this entire area. Same way for smaller tris in group, this time split it i.e. on 2 parts and do the same. Smallest shape forming polys should not be touched. You know entire logic of this. Which modifier do I need?