I'm trying to do a low poly and high poly version to bake down. I attempted modeling it and planning to subsurf the low poly to get the high. Can't seam to get the round surface right and avoiding ngons without adding too much poly. Is there a smarter way to doing what I did?
It looks like while I was composing my answer someone else beat me to the punch. Nonetheless, I will share what I have. I think you get the gist of it already, but there are some slight differences. I hope you'll find it helpful.
Create the edge outline.
Do a spin extrusion.
Make some Loop Cuts.
Scale down with proportional editing enabled. (Sharp falloff)
Simplify the geometry by merging vertices...
...and dissolving edges.
Add a UV Sphere with the appropriate number of divisions.
Delete the bottom verts.
Do Proportional Editing on the UV (hemi)Sphere too. (Spherical falloff)
Delete the lowest edge loop of the hemisphere.
Merge the pedal's vertices to the center hemisphere.
Duplicate and rotate by 22.5° (360° / 16 pedals)
Merge more vertices.
It may be necessary to Remove Doubles from time to time.
Create a tiling section and use the Array Modifier to complete the circle.
An Empty can be used to specify the rotation angle (22.5°).
Enable the modifier settings "Merge" and "First Last" in order to connect the verts of the mesh as one.
Create the geometry for the smaller pedals.
And give them some height.
Here is the final result:
Build the "curves" and only then simplify them
As your main issue is dealing with the lack of curvature, I would approach the problem from drawing at the very beginning an high poly version of the mesh (it's quite geometrical, so it should not be a big deal) that you said you'll need it anyway, and only after simplify it to get the low poly shape with all the curvatures well approximated.
Starting from the lowpoly version and planning to then bevel the edges to make them round can't always reproduce the original geometry.
I would start from the main object, the biggest petals, buy placing a uv sphere and deleting 3 of the quarters:
Then extrude and scale one of the sides. You can now adjust the height. The choice of welding the two meshes constituting the the petals crowns it obviously depends on the needs of your project.
Do something similar for the smaller petals and replicate the meshes with an array modifier to achieve an high poly version of the mesh.
If you kept a rather good topology it should now be quite straightforward cleaning of the redundant edgeloops till you became satisfied with the edge count:
If you stick to quads from the beginning, you'll get a nice flow of the curvature and became very easy to then control the amount of polygons.
Here's a possible result after the simplification. You can obviously go further, but deleting too many faces will not ensure the "curved effect" of the faces. Arcs build in Mesh modeling environments always needs polygons to show up.
And here's the result after another round of simplification. I think after that you'll start losing the appearance of a curved surface.