u/Legitimate-Berry-380

Hello everyone,
I’m still pretty new working with aluminum and trying to improve surface finish.
On this part I keep getting these marks after the finishing pass, especially around the holes and on the curved surface like in the picture. I’m not sure if it’s my toolpath, feeds/speeds, or something else.
I’m using a 10mm DLC coated ball nose end mill, 15k rpm, 3000 mm/min feed rate. Cooling is direct air blast plus pulsed emulsion oil. For finishing I’m using concentric passes counter clockwise with 0.3 mm step over.
I feel like the finish should be much better than this and right now I need too much sanding after machining.
Maybe I’m missing something obvious because I’m still pretty new with aluminum work. Any advice is appreciated, thanks.