Meshes for large geometries too dense

Description

When trying to generate a larger mesh (inlet diameter ~3 cm), the mesh element size did not increase accordingly, resulting in a very dense mesh with too many elements (even when I passed in an mesh size parameter (hsize) to use to set hmin and hmax for MMGS). I resolved the issue by increasing the hausd setting,
tube = remesh_surface(tube, hmin=hsize, hmax=hsize*2, noinsert = False, nomove = False, nosurf = False, hausd = 0.1, hgrad = -1.0,verbosity = 3)

but it would be nice to adjust this automatically based on vessel size.

Reproduction

Example of code that generates a too-dense mesh. Don't include hsize for standard, unmodified svVascularize.

import os
import pyvista as pv
from svv.domain.domain import Domain
from svv.tree.tree import Tree
from svv.simulation.simulation import Simulation
from svv.simulation.fluid.rom.zero_d.zerod_tree import export_0d_simulation
cube = Domain(pv.Cube(center=(0.0, 0.0, 0.0), x_length=45.0, y_length=45.0, z_length=45.0,))
cube.create()
cube.solve()
cube.build()

set_name = 'test_set'
geo_name = 't_1'
# Creating the Vascular Tree Object
tree = Tree()
tree.set_domain(cube)

tree.parameters.set("root_pressure", 2*1333.22)  # in dyn/cm^2
tree.parameters.set("terminal_pressure", 1*1333.22)  # in dyn/cm^2
tree.parameters.set("terminal_flow", 300)  # in cm^3/s
tree.set_root()
tree.n_add(5)
# Wrap a generated tree in a Simulation container
sim = Simulation(tree, name=geo_name)

# Build CFD-ready meshes and identify boundary faces
sim.build_meshes(fluid=True, tissue=False, boundary_layer=True, hsize=0.3)
sim.extract_faces(crease_angle=60.0)

# Construct and write an svFSI configuration
sim.construct_3d_fluid_simulation()
sim.write_3d_fluid_simulation()

# Export a matching 0D model for fast hemodynamic studies
sim.write_0d_fluid_simulation()

Expected behavior

Element size would ideally scale proportionally to the geometry.

Additional context

No response

Code of Conduct

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Reproduce the issue with the supplied Python example, starting at Simulation.build_meshes(..., hsize=0.3) and tracing the remesh_surface call and its MMGS settings. Determine how geometry or vessel size should influence hausd, hmin, and hmax, then verify that larger geometries produce proportionally larger elements without breaking the existing standard case.