You’ve made a lot of extra moves which now strike back. Make a whole design in Blender.
- Add Bezier curve and subdivide once in edit mode. Scale all points Y 0.
- Make your U shaped design: Top Ortho view, grab end points, move Y and rotate as needed.
- Set curve Fill to Front, Bevel Depth as needed (around .15 looks good)
- select all points and flatten curve by setting Tilt (Ctrl-T) 45deg.
- In Object mode, convert Curve to mesh - Alt-C
- In edit mode check for overlapping verts near the middle, scale X overlapping pair of verts if needed.
- select all, move Y away from the object’s origin.
- top Ortho view, press Spin on T-pane, checkmark Dupli. Adjust amount of duplicated elements on T-pane options. Delete doubles, there will be some if you went 360deg.
- to be sure there are no misalignments, select all and scale Z 0
Before Spin, delete one or two loops from the ends of the U shape and add Subsurf modifier if you want ends to be rounded.
Add Solidify modifier or extrude mesh Z.
Edit: to the imported svg - try Delete, Limited Dissolve on all selected verts in edit mode. Chances are, Blender will deal correctly recalculating mesh to n-gons. If there are weird overlapping faces you’d need to do this on each ‘petal’ individually (which doesn’t look like a fun).